Step 1

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.

Step 2

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.

Step 3

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.

Step 4

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.