Sift the confectioner's and granulated sugars together. Add the ground almonds and mix well.
Beat the egg whites until frothy and blend into them the sugar and almond mixture. Add the extract and coloring.
Knead on a marble slab or table top until smooth. Add a little more sugar if necessary to form a stiff paste. Allow mixture to stand for a few hours. Then press small pieces into molds, or shape with your fingers as your skill and fancy dictate. Use the entire recipe at once. The mixture can't be saved for later shaping.