Swiss Meringue Buttercream

• 4 large egg whites
• 1 cup sugar
• 1/2 teaspoon salt
• 1/4 teaspoon cream of tartar
• 2 cups (4 sticks) unsalted butter, at room temperature, cut into 1/2-inch pieces
• 1 teaspoon pure vanilla extract

1. In the top of a double boiler set over simmering water, whisk together the egg whites, sugar, salt, and cream of tartar.
2. Continue whisking until the mixture becomes too hot to touch comfortably, 7 to 10 minutes.
3. Transfer the mixture to the bowl of an electric mixer fitted with a whisk attachment.
4. Beat on medium-high speed until the egg whites hold a stiff peak, about 8 minutes.
5. Add the butter, one or two pieces at a time, beating after each addition until incorporated.
6. Beat in the vanilla.
7. Use at room temperature.

egg whites, sugar, salt, cream of tartar, unsalted butter, vanilla

Taken from www.cookstr.com/recipes/swiss-meringue-buttercream (may not work)