Swiss Meringue Buttercream

Homemade Swiss buttercream is a lightly sweetened frosting made by incorporating butter into a meringue base. It’s less sweet than the American vanilla Buttercream but has the same light and fluffy texture as ermine frosting. Meringue buttercreams can be finicky, though. You must use proper technique to ensure the frosting comes together as it should. But overall it is quite simple to make.

Why this recipe works?

• The egg whites are heated so the frosting is 100% safe to eat.
• The perfect ration of butter to meringue is used to achieve a fluffy, silky frosting.
• This is a base recipe that can be flavored any way you like!

Ingredients

• 1 cup (200 g) granulated sugar
• 4 (140 g) large egg whites.
• ¼ teaspoon salt.
• 1 ½ cups (339 g) unsalted butter, cut into pieces, room temperature.
• 1 teaspoon vanilla extract.

• Combine the sugar, egg whites, and salt in the bowl of a stand mixer. Set the bowl over a saucepan filled with 1 inch of barely simmering water. Whisk gently and continuously while heating the mixture. It should register 150°F on an instant-read thermometer. The sugar should be fully dissolved.
• Transfer the bowl to the stand mixer and fit it with the whisk attachment. Beat on medium speed until the mixture is the consistency of shaving cream and cooled slightly, 1-2 minutes. (if the meringue is warm it will melt the butter.)
• Gradually add the butter, 1 tablespoon at a time, until smooth and creamy. (Only add the next tablespoon of butter once the last one has been completely mixed in.)
• Once all the butter is added, scrape down the sides of the bowl and mix on medium-high and beat until light and fluffy, about 30 seconds.
• Add the vanilla and continue to mix on medium-high until incorporated.

 

NOTES.

• The butter must be softened to about 60°F. It should be soft enough to press an indent with your fingertip but not so soft that it is greasy or melty. Butter that is too soft will turn the frosting into soup.
• Do not begin adding the butter until the meringue has cooled completely! If the meringue is warm, it will melt the butter and turn the frosting into soup.
• If your frosting curdles and won’t smooth out with 5 minutes of mixing, don’t panic. You can salvage it by heating the side of the bowl with a hairdryer while the mixer is running. Do this until the frosting starts coming together, turn the hairdryer off and continue beating until the frosting is light and fluffy. Or you can place about ⅓ cup of curdled frosting into a microwave-safe bowl and microwave it for about 15-30 seconds. Give it a good whisk then add it back to the main bowl of frosting. Beat on medium speed until the frosting comes together.
• If your frosting is loose and soupy, it can be salvaged by placing the bowl and whisk attachment in the refrigerator for about 20 minutes. Then rewhip the frosting until it is light and fluffy.