Ingredients
2 large egg whites, plus more if necessary
4 cups confectioners' sugar (sifted, then measured), plus more if necessary
Juice of 1 lemon
Liquid food coloring in desired colors
Preparation
Put egg whites in the bowl of an electric mixer fitted with the whisk attachment; beat until stiff peaks form. Add sugar, lemon, and juice; beat 1 minute. If too thick, beat in more egg whites; if too thin, beat in more sugar.
Divide icing into small bowls and tint with a few drops of liquid food coloring as desired. Use immediately.