1 c. sugar
5 tbsp. cold water
1/4 tsp. cream of tartar
1/4 tsp. salt
2 egg whites
1 tsp. vanilla

Combine sugar, water, salt, and cream of tartar in a saucepan. Stir to dissolve sugar. Place over high heat; cook to a full rolling boil. Place egg whites in small mixer bowl. Beat while pouring hot syrup over egg whites. Beat on high speed until well blended. Reduce speed to medium. Beat until mixture is of spreading consistency. Add vanilla; beat to blend thoroughly.

Note: This frosting does not form a dry crust but remains moist. For variety, add 1/4 teaspoon peppermint flavoring and several drops of red food coloring to tint a delicate pink, in place of vanilla.