Silken white chocolate buttercream is an essential icing in any baker’s arsenal. This one starts with a base of Swiss meringue, wherein egg whites and sugar are mixed in a bain marie until they reach 140º. They’re then whipped to fluffy peaks and flavored accordingly. Use this icing to frost a summery Lemon Curd Layer Cake.
- 3⁄4 cup sugar
- 3 egg whites
- 20 tbsp. unsalted butter, softened
- 2 oz. white chocolate, melted and cooled
- 1 tsp. vanilla extract
- 1⁄8 tsp. kosher salt
- Place sugar and egg whites in the bowl of a stand mixer and set it over a saucepan of simmering water; stir mixture until egg whites register 140° on an instant-read thermometer. Remove bowl from saucepan and place on stand mixer fitted with a whisk; beat on high speed until meringue is cooled and stiff peaks form. Replace whisk with paddle and add softened butter to meringue; beat until smooth. Stir in white chocolate, vanilla, and salt.