Pink – Chop beets and cook them in a small amount of water, or use the juice from canned beets. Concentrate the color by boiling it down or microwaving it into syrup (but be careful not to burn it). Extra syrup can be kept in small containers in the freezer.
Red – Use a lot of concentrated beet juice. Allow it to deepen in color for two days in the freezer.
Yellow – Add turmeric (available in the spice section of your supermarket) to white frosting. Refrigerate it and allow it to deepen overnight. & Add a small amount of lemon extract to disguise the taste of the turmeric.
Green – Cook chopped spinach only to a bright green stage. Puree it in the blender. Strain the spinach in a little cheese cloth to make it stronger. If you prefer a darker green you can substitute the spinach puree for the vanilla and / or the milk. (This coloring will have some green specks, but it works very well for trees, leaves and grass.)
Purple – Boil chopped red cabbage in some water. Concentrate it as directed for the beets. Keep the syrup in the freezer.
Blue – Adding baking soda to the cabbage juice will make a steely, gray-blue.