- 4 1/2 Cups confectioners sugar
- 4 pasteurized egg whites
- 1/2 Teaspoon cream of tartar
- 1 Teaspoon vanilla extract
- Food coloring, if desired
In a large metal bowl of an electric mixer, use the whisk attachment to beat the egg whites, cream of tartar and vanilla on high speed until frothy.
Adjust mixer speed to low. Slowly add confectioners sugar.
Increase speed back to high. Mix icing until thickened and there are glossy, stiff peaks.
To add food coloring, separate icing into bowls and add the desired amount of coloring to each bowl, incorporating using a rubber spatula.
While frosting cookies, cover icing you are not using with plastic wrap, as royal icing dries very quickly.