Italian Buttercream Frosting
1 1/4 c. plus 1/3 c. sugar
1/2 c. water
8 large egg whites, at room temperature
1 tsp. cream of tartar
1 1/2 lbs (6 stikcs) unsalted butter, cut into pats
Place the 1 1/4 c. sugar and the water in a saucepan. Stir to set the sugar and bring to boil over medium heat and wash the sides of the pan. Place the whites in a grease-free mixing bowl and whip until frothy. Add in the cream of tartar and continue to whip until soft peaks form. Add in the 1/3 c. of the sugar. Continue whipping until stiff, glossy peaks form. Meanwhile, keep boiling the sugar syrup until the temperature reaches 248 degrees F. When the syrup is ready, reduce mixing speed of the whites to medium and slowly pour in the hot syrup into the egg whites. Try not to get any of the syrup on the sides of the bowl or hard sugar balls may form in the meringue. Continue to whip until cooled, which may take up to 15 minutes. Add in the pats of butter and whip until combined, smooth and the butter is incorporated.
