Italian Meringue Buttercream

Italian Meringue Buttercream
Makes 4 1/2 cups
Use this to frost the Pretty Petits Fours, or your favorite layer cake. Its important that your egg and syrup mixture come to room temperature before adding the butter otherwise your egg whites will deflate. Make sure your butter is very soft, I leave mine out over night.

1 1/4 cups sugar
5 large egg whites
Pinch of cream of tartar
1 pound (4 sticks) unsalted butter, room temperature
1 teaspoon pure vanilla extract

In a small saucepan over medium heat, bring sugar and 2/3 cup water to a boil. Continue boiling until syrup reaches 238 degrees.on a candy thermometer (soft-ball stage).

Meanwhile, place egg whites in the bowl of a standing mixer fitted with the whisk attachment, and beat on low speed until foamy. Add cream of tartar, and beat on medium-high speed until stiff but not dry; do not overbeat.

With mixer running, add syrup to whites in a stream, beating on high speed until no longer steaming, about 5-10 minutes. Add butter bit by bit, beating until spreadable, 3 to 5 minutes; beat in vanilla. If icing curdles, keep beating until smooth.