The Best Swiss Meringue Buttercream using the handy 3:2:1 ratio of butter, sugar and eggs. Servings: Enough to fill 4 dozen regular macarons. Double recipe to frost a round 6 inch cake.
Bring a small pot of water to a boil.
Place egg whites and sugar into a heat proof bowl. Stainless steel is light and safe.
Gently whisk the whites & sugar mix over the boiling water.
Pay attention to whisking the mixture when it starts getting hot, you don’t want to cook the eggs.
Whisk the mixture until the temperature reaches 160F*
Pour the mixture into the Kitchenaid mixer with the balloon whisk attached. Whip on low to start, then increase to medium.
Once the mixture is stiff and the bottom of the bowl is cool to the touch, stop mixer. Change the whisk attachment to the paddle attachment.
Add butter a little bit at a time while beating with the paddle attachment on medium speed.
The mixture might look curdled or separated for a while but keep mixing. It will all come together.
Add any extract, flavourings or food colouring if desired. Whip until incorporated.
Using a flexible spatula, fold out excess air in the frosting so that it can be piped or spread smoothly.
*This is the temperature generally regarded to be able to kill salmonella in eggs. Caution should always be taken when serving meringue based desserts to children, pregnant women or those with a compromised immune system.
**Store the leftovers in an airtight container until use for a maximum of 5 days. It can also be frozen.
***Before using, place on counter until it comes to room temperature, then re-whip with a paddle attachment until it becomes fluffy again.