Mix flour, salt and cream of tartar in medium saucepan. Add water and oil; mix well. Add 20 drops of desired food color.
Cook about 5 minutes on medium heat, stirring constantly until mixture holds together. (Have a grown-up do the cooking.)
Remove from heat. Scrape dough onto wax paper to cool. Knead slightly until dough is smooth.
Store in an airtight container. May be kept for 2 to 4 weeks.