1. Put sugar and egg whites in the heatproof bowl of an electric mixer, and set over a pan of simmering water. Whisk constantly until sugar is dissolved, and mixture registers 140F on an instant-read thermometer. 2. Transfer bowl to an electric mixer fitted with the whisk attachment. Beat on medium-high speed until fluffy and cooled, about 10 minutes. Continue beating until stiff, glossy peaks form. 3. Reduce speed to medium-low; add butter by the tablespoon, beating well after each addition. Beat in vanilla and coconut if making buttercream for filling. Buttercream can be refrigerated in an airtight container up to 3 days or frozen up to 1 month. Bring to room temperature before using; beat on lowest speed until smooth, about 3 minutes. ---------------------------------------------------------------------------
Nutrition
Ingredients
