It’s easy to add a little food color “paint” to your shortbread to highlight designs. You will need:
Freshly baked and thoroughly cooled shortbread
1 egg white
½ cup powdered sugar
paste-type food colors
dessert size plate, preferably white
Note: It is important to use clean brushes that are reserved for use with foods ONLY. Many watercolor and other paints contain ingredients that may be toxic.
In a small bowl, whisk the egg white until it is frothy, then stir in the powdered sugar. Brush the tops of your shortbreads with a thin layer of this glaze. This will seal the top of the cookies, creating a “ground” for the painting you will do with the food coloring. Allow the glaze to dry completely.
Prepare your pallet. Using the tooth picks, place a small dab of the different food colors around the edge of the plate. Start with pink, red, orange, yellow, green, blue, purple, etc., moving through the spectrum.
When the glaze on your shortbread is completely dry, paint the cookies whatever colors you want from your food color pallet. Use water to thin the colors. You can mix the food colors to any shade in the empty center section of the plate. Generally, pale colors look best.