1 16 ounce package powdered sugar (4 cups) 3 tablespoon meringue powder* ½ teaspoon cream of tartar ½ cup warm water 1 teaspoon vanilla
*Tip
Meringue powder is a mixture of pasteurized dried egg whites, sugar, and edible gums. Look for it in the baking aisle of your supermarket or at a specialty food store.
