1/2 c. cornstarch
3/4 c. cold water, divided
2 c. hot water
2 tsp. boric acid
1 tbsp. glycerine
Tempera paint or vegetable color

Mix cornstarch and 1/4 cup water. Add hot water. Stir and cook over low heat until mixture boils. Remove from heat. Add 1/2 cup cold water, boric acid, and glycerine (makes it dry slower). Add tempera paint or vegetable color, as desired. Store in airtight container in the refrigerator.