Put mixture into an ice cube tray and set aside to harden. Break or cut into pieces. For each color you would like, put two tablespoons of hot water and one cup of soap flakes into a bowl. Add as many drops of food coloring to the mix as you think necessary. Stir the soap mixture until it thickens.
Press spoonfuls of the first color of soap into sections of the ice tray.
Mix enough soap in other colors to fill the entire tray, repeating the first two steps. Let the soap crayons dry for one or two days. Gently bang the ice tray to loosen the crayons. Place broken up crayons in each cupcake cup. Bake in a 350 degree oven until the crayon pieces have melted.