Dealing with hollow macaron shells? Here are the top reasons why your French macarons are hollow and how to fix them.
The Trouble with Hollow Macarons
Most bakers start to notice the issue of hollow macarons later in their macaron baking journey. When most bakers begin baking this little French treat, most are likely trying to overcome common hurdles like cracked macaron tops and bumpy shells. As a result, most tend to covet smooth non-cracked shells and frilly macaron feet above all else. But as their macarons start looking better - on the outside anyways - they realize there's a hidden issue that lies deep within their macarons - hollow shells.
Do Hollow Macarons Go Away with Maturation?
Severely hollow macarons cannot be fixed with maturation. If most of the body has burst out of the shell and into the feet or sank down to the bottom causing a huge gaping hole, no amount of maturation will really help these types of macarons. Pressing into the back of the shells in order to push the body back up to the top - which some bakers do to deal with hollows - may be a temporary solution. But, ultimately, it's worth fixing hollow macarons since there is something inherently wrong with the baking technique.
A truly non-hollow macaron is not hollow even before filling and maturation as shown in the video above. If it's just a small gap in the macaron shells, these do benefit from filling and maturation, yay! You'll find that they can completely go away after 24 hours of maturation.
Should I Fix Hollow Macarons?
Having said of all that, it's important to remember that hollow macarons are not a problem for most people who eat your macarons unless they're macaron snobs and to which I say, why are you sharing your precious babies with those people anyways 🙂
All kidding aside, although hollow macarons may taste the same as non-hollow ones, severely hollow macarons are more fragile and lack the distinctly chewy texture of a full and fluffy macaron. Those are two of the reasons why you might want to work on your hollow macarons. But if you're obsessed with non-hollows for the glory, save yourself the frustration. It's important to remember that no matter what they look like, macarons are for eating!
For those who are keen on fixing this problem. Below are some key issues to look out for.
How Do I Fix Hollow Macarons?
Hollow macarons can be fixed by whipping the meringue to the correct stiffness, folding the batter to the ideal consistency during the macaronage stage, rapping the tray after piping, using the correct tools, baking at the optimal temperature and possibly the addition of a "secret" ingredient.
Meringue Stiffness
Over-beating the meringue can cause macaron shells to deflate while baking, resulting in a hollow shell. A good stiff meringue is required for my best recipe, however, over-beating the meringue can have an adverse effect and lead to hollow macarons. This is especially true if your macaron looks almost perfect in every way except for a little gap inside the shell.
If your macarons are looking fabulous in every way already (dainty feet, smooth tops), then this fix is for you. Beat the meringue up to the stiff peaks stage and stop immediately once it has been reached. If you are worried about overwhipping, you can skip the mixer and whip the meringue by hand. Yes! It can be done, check out How to Make Macarons without a Mixer and fancy tools.
How Stiff is Stiff Peak?
Beat the meringue until a small peak points upwards when you pull the whisk out of the meringue. The peak can be small! If you beat until a big clump of egg whites can point upwards, you are probably over-beating. This is worth mentioning as some of you may have been trying to test the peaks with a lot more meringue than is needed.
Another way to scale back on how much you have been beating your meringue is to test the bowl by tipping it upside down. Once the egg whites can cling securely onto the bowl without slipping and you have a SMALL stiff peak, stop beating the meringue.
It's very important to create a stable foundation for your macarons and a lot of it starts with the meringue. The speed at which the meringue is whipped and the temperature of the ingredients also play a role. Take a look at the following post to learn more on how to make meringue for use in macaron baking.
FURTHER READING: HOW TO MAKE PERFECT MERINGUE FOR MACARONS
Folding During Macaronage
The macaron batter should be properly deflated to prevent hollows. If you tend to over-beat the meringue, this will help you counteract that. In the beginning of our macaron baking journey, we were told to be careful with deflating the batter. "It's better to under-fold than over fold,"...etc. But that's where a lot of hollow macaron problems begin - from an under-deflated batter. When you're folding the batter, you don't need to baby it as much as you think. Here is a video on how to fold properly to avoid hollows:
Proper Macaron Batter Consistency
On the flip side, over-folding can also cause hollow macarons and feet that are widely spread apart. When folding during the macaronage stage, constantly test the batter using the Figure-8 test in the video above. The batter should flow steadily without breaking but it should not be too runny either. Aim for a thick honey-like consistency. Here is what to look for in terms of consistency during and after piping:
Rap Tray
Rapping the tray after piping will further eliminate the small gaps in the shells that lead to hollows. Make sure you are tapping it hard enough against a hard surface. In the macaron class I took, the instructor literally dropped the baking trays from waist level down onto the floor. It's quite a violent action and sometimes the shape of the shells do change after rapping. For that, I recommend piping on Silpat mats which are great for retaining the shape of the macaron. Pop any remaining bubbles with a toothpick.
Silpat Mats
Silpat silicone mats are great for retaining the macaron's shape. There are many cheaper silicone mat alternatives out on the market now but I recommend using the Silpat brand. I trust them to have the highest degree of food safety. Also, they are reliable for conducting enough heat to reach the bottom of the macaron shells which helps with reducing hollows. Disclosure: Affiliate Links
Silpat Mats: 11 ⅝ X 16 ½ is the size I use in all the videos showing one single mat on a pan. SILPATS are is the only mat brand I use for baking macarons. This mat has no preprinted templates on it so it's great for using over my free macaron art templates.
Toaster oven sized Silpat mats: are perfect for counter top ovens. I sometimes place two of these on one tray to bake two different sized macarons shells at once. You can easily take out one mat earlier once it's done, leaving the other mat to bake longer. SILPATS is the only mat brand I use for baking macarons.
Bake Time & Temperature
Meringues and by extension, macarons, love heat! Give it as much oven love as you can and you'll see less hollow macarons in your kitchen. You can do this by using a:
a.) higher temperature OR
b.) lower temperature with a longer bake time
325 F for 12-14 minutes is a great place to start. (I know of a baker who likes to go even higher at 350 F for 10 minutes.) I must admit, this is quite a high temperature. Most readers have found that 325 F or higher can cause their shells to become browned so another temperature/time combo I can recommend is 275 F for 18 minutes. You can play with the time/temperature combinations. For every 25 F, compensate with a 2-3 minutes change in the inverse direction.
Some Recommended Baking Temperature and Times for Perfect Macarons:
350 F for 10 minutes - suitable for spacious large ovens
325 F for 12-14 minutes - standard starting point for use with my recipe
300 F for 16-18 minutes
275 F for 18-20 minutes - suitable for smaller ovens with small compartments
FURTHER READING: HOW TO USE YOUR HOME OVEN PROPERLY TO BAKE MACARONS
Silpats VS. Parchment VS. Teflon
Some bakers complain about hollows when using Silpat mats and have given up on them completely even though Silpats produce much better results in terms of retaining the macaron's shape. Sometimes Silpats don't perform as well for fully fluffy shells because of the related issue discussed in the last section: heat. The mats are thicker than parchment paper and don't conduct heat nearly as well.
There are a few adjustments that can be made to compensate for this:
- Use better heat conducting baking pans.
- Put it closer to the heat source if your oven's heating coils are on the bottom.
- Try Teflon paper which better conducts heat.
- Keep a pizza stone underneath the baking tray.
Heavy-duty baking pans: This is the cookie sheet I use. It's constructed of aluminized steel, the material of choice for commercial bakeries. It is also heavy duty so it won't buckle while baking . It is also rimless allowing even air flow to the macarons.
Teflon baking sheets: These are great for conducting heat and provides macaron shells the heat that some ovens lack. A great compromise between parchment paper and silicone.
Pizza Stone: A pizza stone in the oven can help stabilize oven temperature for temperamental ovens and provide heat from the bottom.
Convection VS. Non Convection for Macaron Baking
You don't have to get too hung up over whether or not to use the convection setting to bake macarons. I've had both types of ovens and they have both performed equally well for baking macarons. If your batter is at the right consistency, you can bake non-hollow macarons in both a convection or non-convection oven granted that you have found an optimal temperature and bake time. Consistent high temperature is key using the tools provided above. Keep an external oven thermometer to keep track of the temperature in the oven. Keep oven doors closed as much as possible and do a longer pre-heat if needed to reach that consistent temperature. Sometimes it takes a little longer to pre-heat to a consistent heat level.
Magic Ingredient for Non-Hollows?
Although, technically, you should be able to overcome hollow macarons with the right techniques as mentioned above, there is one special ingredient you can consider. There's a lot of buzz around adding egg white powder to the dry ingredients to help combat hollows. I haven't tried it yet but it's something that some bakers have discovered worked for them. If all the above fixes don't work for you, you might want to give it a try.
Please note, egg white powder is NOT the same as meringue powder. Meringue powder contains a mixture of sugar, acids and flavorings while egg white power is just purely egg albumen.
My Secret for Testing Macaron Doneness
If you lower the oven temperature as per above, it's important that you bake for a longer amount of time, otherwise, the meringue will collapse after it cools. How to test the macaron for doneness? I'll cover it in an upcoming post. Stay tuned!
I hope you found this post useful and let me know below if you have any further questions.
XOXO,
Mimi
[pt_view id="f56aea0p7b"]
Grete says
Hello!
First of all, your troubleshooting guide is the best by far on the internet! Thanks for sharing.
Now, I've been making macarons for 14 years or so, more intensely for the last 3 years, maybe. There have been times when they have come out perfectly, once I didn't even have any hollows, but it was like 3 years ago and happened accidentally, so I'm not sure, what I did right then :D. But after that it has always been one problem or another. Hollow macs are the most common, but also a few cracked macs per tray (other tray's might be just fine except for the hollows), sometimes they are flopsided (again, most trays can be normal, but then on one of them, they look funky). But they have been presentable most of the time. But now I have a whole other problem. I recently changed my almond flour. With the almond flour that I used before, my macarons were never super smooth despite the fact that I grounded them with powdered sugar and sieved them. I purchased a new, super-super fine almond flour, that leaves the macarons perfect in regards of smoothness. But, when I used the same amount of it (I always use grams, not cups), the batter looked weird. It didn't matter how much I macaronaged it, it was thick. The macarons looked pretty good in the oven, but as soon as I took them out of the oven they started to sink in and they looked like the surface of the moon. No cracks or anything. It had NEVER happened to me before and I couldn't even find any info about it from the internet. Also, they were kind of wet when eating them. Now, I have used your recipe (I usually double the amount) for the last few years and when I usually use 130g of almond flour, now I use 100g and then it looks like before (they are still hollow, but they don't sink like that). I have used different baking times and temperatures, ranging from 135-180 Celsius. But I pretty much can't use over 135 degrees (275 F) at all, because then it immediately starts to brown. And even at 275 F it starts to brown after 15 minutes, but according to your instructions it should need at least 18 minutes. And I do believe that my reason for shallow macarons is the oven temperature. Also, when thinking about the fact, can they be raw, I also baked them at 180 degrees and varied with 10 and 15 minutes, but they still were wet and sunk in after removing from the oven. But then they were also brown and pretty much caramelized.
So, my question, after such a long comment (sorry!) is, have you ever heard from anyone else, that they have to change the amount of almond flour used when they have switched brands? A few of your tricks I haven't used yet, so I'll be sure to try them out with my hollows.
Thank you!
Mimi says
Hi Grete,
I actually have not heard of a situation in which a different brand requires a different amount of almond flour. I usually make my own almond flour and find very consistent result this way. Have you tried? It seems like it may be worth looking into it from all the trouble you're having. I know you have tried varying degrees of temperature but may I suggest not overwhipping the meringue and not overfolding the batter. Sunken macarons may not come from strictly from low temperatures. Let me know how you're doing with that.
XOXO,
Mimi
Mony says
Hi there, I tried use 300°F and bake 20 mins but never come clean. Then I add three more mins one, then, they are over baked. Sigh!
Mimi says
How are the insides? You might want to give the shells a bit more heat from the bottom or use better conducting paper/pan combo. Some tools to try include Teflon paper/parchment paper and the better heat conducting pan like USA pan. I have that item listed in my shop.
XOXO,
Mimi
Abby says
Hi Mimi,
Thanks so much for all of your helpful blogs about Macaron Troubleshooting. I'm having some issues with big bubbly feet that grow really fast in like the first half of the bake time. They also tend to grow a little outwards. The batter is the right consistency I believe and they don't crack. I'm baking them at 285 for 15 minutes? Should I lower it or am I doing something wrong with the meringue. My sisters bday is coming up soon and I really want to make these for her. If you could help me I would greatly appreciate it because I want to master these macarons so badly. Also the recipe I'm using is by Ro Pansion, its the unicorn macaron one. If you have any tips I would love them. Thanks! 🙂
Mimi says
Hi Abby,
Sorry for the delay. I hope you were able to get your answer solved. The best thing to do is always check with the author of the recipe you're using. They will be the best person to guide you through the unique characteristics of their recipe. Happy Baking!
XOXO,
Mimi
Susie says
Hi Mimi,
I seem to have a problem where my shells look great on top, the feet start to rise...and then they start to lift off the silpat mat! Some macs look fine with ruffled feet on one side and then the other side has raised so it looks like a UFO! Others lift completely and don't stick to the mat and when I take them out they deflate a little bit but the feet never spread. I honestly haven't had this problem before following your recipes and it's very hard to find out more online as it doesn't seem to exist? The macs are partially hollow (holes in some areas and small gaps at the top in others). I know it might be hard to say but any ideas what could be happening? Thank you!
Mimi says
It sounds like an issue of concave macarons. Have you read my troubleshooting guide? It will cover that specific problem and how to fix. XOXO, Mimi
Toni says
Hey,
Great tips! So in short, if my macarons have a lot of height, feet going upwards, and are hollow, I should whip a little less?
Mimi says
Without seeing your exact results and baking process, I can't pinpoint exactly where your hollows are coming from those are the areas I would work on: whipping less and temperature control. Enough heat for sufficient amount of time.
XOXO,
Mimi
Liz says
At what temperature should we bake the macarons? I think you said in the video to preheat to 300 (if i heard it correctly 😅) but in the text it says 320
Mimi says
I'm sorry for the confusion! It should be 320F I really wish I could change that part! Every oven is different so you'll still need to make adjustments as you bake a few trays and see how macarons bake in your oven. Take a look at my oven guide if you have a chance. XOXO, Mimi
Maya says
Thank you for the detail explanation on trouble shooting hollows.
Hoping you can give me some pointers before my next batch. My cookies looks perfect, it’s got nice height and nice feet. But they are hollow, and really sticky, can’t get them off my Silpats. I did the wiggle test to check for doneness before taking them out.
Cookies were baked for 14 mins @300F (this is giving some colour to it already too) My oven only have top coils, maybe I should try the pizza stone trick.
Thank you!
Mimi says
Hi Maya,
Just as an experiment, have you tried baking on Teflon paper or parchment. That will give you a better idea of whether or not you are getting enough heat to the shells. (Silpats can be a bit harder to conduct heat). After that, try not to overbeat the meringue too much and then use a longer baking time and slightly lower heat.
XOXO, Mimi
Maya says
Hi Mimi,
Thank you for the experiment suggestion. No I've not tried baking on Teflon paper or parchment. So what you are saying is, try it with the paper first, and when that works then I will have better success with Silpats with longer baking time and slightly lower heat?
Mimi says
Hi Maya,
Yes, if it works on Teflon and parchment, then your preparation technique is probably on the right track. Then you can try with Silpats with a longer bake time and slightly lower heat. If you don't have Teflon or parchment, just go right ahead do the second part of the suggestion. It should help.
XOXO,
Mimi
Mary says
Hello! Thank you for your helpful posts and trouble shooting guidelines. I have been getting really hollow macarons in recent bakes, I can see through them and I’m struggling to figure out what I’m doing wrong. I’m trying to make sure I don’t over whip the eggs or over mix the batter, but it doesn’t really change the hollowness. 😔
Mimi says
Hi Mary,
How are the feet to your macarons? If they spread outwards and have a huge hollow inside, then you should dry whipping the meringue a bit stiffer and then fold a little bit less than you usually do. If the feet are nice and dainty already, then scale back on the whipping and folding.
XOXO,
Mimi
Dee Nargi says
Thank you this is all helpful. How much of the dried egg whites would you add to the dry ingredients?
Mimi says
Hi Dee,
Happy you found it useful. For my recipe, you can add 1/4 tsp - 1/2 tsp.
XOXO, Mimi
Mokshita says
There is so much knowledge... Thank you mimi.. I just wanted to know that should i buy oven thermometer?.. As my oven is super hot even at 50 degree.. Its a home oven.. Its my mom's oven.. It was brought 25 yrs back.. It only has 50,100,150....,300 degrees celsius options.. And at 50 degree I baked macarons the feet spread.... Plz guide.. Thank you
Mimi says
Hmm... 50 degrees is not too high in fahrenheit so I'm not sure if I am reading that correctly. Please read my oven guide on some adjustments you can make to compensate for different oven conditions. XOXO, Mimi
Nina says
Thank you so much for all the useful information on your site about macarons! I have been making them for about a year and kept having issues with them being hollow. I tried your recipe and tips this weekend and finally got non-hollow macarons!
Mimi says
Hi Nina,
I'm so happy to hear that! It really makes me happy to hear about this final step that helped you cross the finish line! Yay!!!
XOXO,
Mimi
Laura says
I am so glad I found your blog, you are very clear with very detailed information. I was reading about the contain of corn starch in powdered sugar, I would like to know what brands you use, I am using one that is corn free and is with tapioca starch because this is more expensive.
Thank you from your faithful follower
Laura
Mimi says
Hi Laura,
Thank you for the feedback. I'm happy you found it useful. Tbh, I buy any kind of powdered sugar that is on sale. They all work well for me. I generally use Rogers since it is readily available. Almost all the powdered sugar found at the major grocery stores here in Canada all contain corn starch as an anti-caking agent.
XOXO,
Mimi
Eugene says
Thank you for the great information all the time. I have been in Macarons journey for a while now and I am still struggle with hollow macarons often. Is it convection setting when you said baking temp 325°f? I usually bake 300°f with convection, I am thinking maybe temp is kinda low after I read this post....
Mimi says
There are so many factors to consider and even in terms of the temperature, it also depends on how your own oven operates. Every oven is different. I would try using a higher temperature and rule that out before making other changes. XOXO, Mimi
Megan says
Hello!
I have been trying to make macarons for a couple months now. I have finally gotten the shape of the macarons but they are completely hollow on the inside!!!
I tried every temp you listed but my macarons are still hollow. In the oven they rise suspiciously high and fast and lower a bit later. When they come out of the oven they look perfect with the feet and everything. I dont understand.
I am living in Colorado which is a higher altitude. Please do you have any suggestions? I think my batter is perfect but the oven thing is tripping me up. Even 300-275 is giving me hollows😭😭😭
Mimi says
Hmm... I don't know muuch about high altitude macaron baking. Perhaps if you have some insights to share with us that would be great 🙂
XOXO,
Mimi
Kristie says
I live in Colorado and YES!! This is my exact experience!
Jane says
High altitude friends! I feel your pain with the uncertainty. I had a ton of problems with hollow and overall texture. I've tried multiple recipes, temperatures, macronage techniques. I still get hollows, but the void has gotten MUCH smaller. I think my problems now are related to slightly over beaten meringue.
I use Mimi's recipe, but with 60g egg whites and 54g granulated sugar. This adjustment was after some experimentation informed by altitude corrections I found on the Betty Crocker website for other air leavened desserts (angel food cake). At higher altitude, water boils faster (as I'm sure y'all know), so I tried making the macaron batter "wetter".
For my little non convection oven, I do about 325F for 10 minutes. (I crank it up to 350 and then knock it down to 325 before I put them in).
Like I said, I have seen improvement on the hollow issue, but it has not fully gone away. I'm really curious to see if other high altitude people can make the French method work. If you try out more egg white in the recipe, I'd love to hear how it goes!
PS: I have some friends in Colorado who have had success using Italian meringue. It might be worth a try. (I'm still too lazy to do it)
Roua Hammoud says
Hi Mimi
I wondered if the inside of macaron shell should be dry when you take them from the oven. I noticed that me macaron are pretty full when I get them out from the oven but tend to develop a hollow when they colon down. What am I doing wrong? My macarons interior are quite chewey and moist when right after baking. Please help!!!
Mimi says
Yes, it should be dry inside when you break it open. If it's still wet, then they will collapse after cooling. XOXO, Mimi