Mix together all the ingredients, except the food coloring, in a medium saucepan.
Cook over low/medium heat, stirring. Once it begins to thicken, add the food coloring.
Continue stirring until the mixture is much thicker and begins to gather around the spoon.
Once the dough is not wet, remove and put onto wax paper or a plate to cool.
After cooling (30 minutes) knead playdough for a few seconds.
Store in an airtight container in the fridge!
The above will make you ONE large ball of playdough. I usually make it repeatedly for however many colors I want (so if you want 6 big balls, know that you will need 6 times the ingredients listed above, but you need to make them separately).