3 3/4 c. confectioners sugar
1/4 tsp. cream of tartar
3 egg whites

In small bowl with mixer at low speed, beat 3 3/4 cups confectioners sugar, 1/4 teaspoon cream of tartar and 3 egg whites until just mixed. Increase speed to high and beat until mixture is so stiff that knife drawn through mixture leaves clean-cut path.