How to Make Swiss Meringue Buttercream: the Foolproof Method to Make it Perfect at Home!

Swiss meringue buttercream is renowned among baking aficionados for its silky texture and not-too-sweet flavor profile, making it an ideal choice for frosting cakes and cupcakes. Unlike other frostings, it is smooth and buttery without being overly heavy.

What is Swiss Meringue Buttercream?

Swiss meringue buttercream (SMB) is a type of frosting that combines egg whites and sugar, which are heated and then whipped into a meringue, and then mixed with butter and flavorings like vanilla. This frosting is preferred for its stability and creamy texture, which holds up well under fondant and smoothens easily over cakes.

Ingredients

To make Swiss meringue buttercream, you will need:

• 300 grams of egg whites
• 400 grams of sugar
• 1 teaspoon of vanilla sugar (or extract)
• 400 grams of unsalted butter, at room temperature

Method

Begin by combining the egg whites and sugar in a heatproof bowl. This mixture will need to be heated, so choose a bowl that will fit snugly over a pot of simmering water (bain-marie). Place the bowl over a pot of simmering water, ensuring the water does not touch the bottom of the bowl. Constantly whisk the mixture to prevent the egg whites from cooking and to help the sugar dissolve completely. This step is crucial for a smooth buttercream.

Once the sugar has dissolved completely (you can test this by rubbing a bit between your fingers; it should feel smooth, not gritty), remove the bowl from the heat. Using a stand mixer or hand mixer, whisk this mixture on high speed for about 10 minutes, or until the meringue forms stiff peaks and the mixture has cooled significantly. Add the vanilla sugar or extract to the meringue and mix briefly to incorporate. Then, gradually add the room-temperature butter, a few pieces at a time, while continuing to beat. The mixture might look curdled at this stage, but keep beating—it will become smooth. Continue to beat the mixture until it becomes thick, smooth, and glossy. This may take several minutes. Once the desired consistency is achieved, your Swiss meringue buttercream is ready to use for decorating cakes and cupcakes.

How to Make It White

To achieve a whiter shade in your SMB, use butter that is very pale in color and add a tiny amount of purple or blue food coloring to counteract any yellow tones. Another method is to use clear vanilla extract instead of regular vanilla, which can darken the mixture.

Storage and Shelf Life

Swiss meringue buttercream can be stored at room temperature for a day, provided it's not too hot or humid. For longer storage, keep it in the refrigerator for up to 2 weeks or freeze it for up to 3 months. Always let it come to room temperature and rewhip before using to restore its texture.

Swiss Meringue Buttercream vs. Regular Buttercream

The main difference between Swiss meringue buttercream and regular (American) buttercream is in the preparation and texture. American buttercream is simply butter beaten with powdered sugar, which tends to be sweeter and denser. Swiss meringue buttercream, by contrast, is smoother and lighter due to the meringue base.

Common Mistakes and Fixes

– Buttercream is too runny: This often occurs if butter is added when the meringue is too warm. Chill the mixture for 20 minutes, then rewhip.

– Buttercream curdles: This happens when the butter is too cold. Keep mixing, and it should come together.

– Too buttery or heavy: Add a pinch of salt or a few drops of lemon juice to cut through the richness and lighten the flavor.