SWISS BUTTERCREAM

Steps:

• Whisk the egg whites and sugar in the bowl of a standing mixer set over a pot of boiling water. Whisk constantly until the sugar has dissolved completely and the egg whites feel hot to the touch, or a thermometer reads 140˚F.
• Transfer the bowl to a standing mixer fitted with a whisk attachment and whip the egg whites on high speed until they have formed a meringue and the bowl has cooled to room temperature, 5 to 7 minutes.
• Remove the whisk attachment and switch to a paddle attachment on the mixer. Begin adding the butter in small amounts while the mixer is on medium-high speed. (As you are adding the butter, particularly if you add it quickly, the icing may start to look as if it's curdling. This is normal. Just finish adding the butter and continue to beat the icing until it is smooth and fluffy.)
• Once it is finished, the icing should have a smooth, shiny appearance. Flavor it as directed and use it immediately, or keep it in an airtight container in the refrigerator for up to 4 days.
• For a crisp, sharp peppermint icing, add 2 tablespoons of peppermint extract, and mix well until combined. You can use it for a marvelous seasonal treat for Christmas parties, as the pristine white icing looks almost like snow atop a chocolate cupcake and then adorned with pieces of crushed candy canes.