Use this icing to decorate your favorite sugar cookies recipe.
Put sugar in a mixing bowl. With the mixer running, slowly add egg whites, allowing the sugar to absorb them. Add just enough egg whites to get a smooth consistency (you may not need all 6). If icing becomes too thick, thin with lemon juice.
Divide the icing among several small bowls and tint with a small amount of paste or powdered food coloring. Mix well for an even color.
Spread a thin layer of base icing on the cooled cookies, using a flat metal spatula. Allow to set uncovered for about 1 1/2 hours or overnight. Cover bowls of leftover icing with plastic wrap, making sure the wrap touches the icing. This prevents it from forming a crust and drying out.
Decorate the cookies using pastry bags and small tips. Thicken the icing with a bit of confectioners' sugar before putting it in the pastry bags.
We used Ateco food coloring and pastry tips. Some of the colors used were lemon yellow (#1220), teal green (#1137), Georgia peach (#1138), and seafoam green (#1128).