2 cups flour
1 cup salt
3 tsp cream of tarter
2 tbsp oil (we used apricot oil b/c it is good for the skin and we had some in the cabinet anyway, but olive oil works just as well)
2 cups water
Mix in a pot over moderate heat. You probably should add in the food coloring while the dough is still liquid-ey and easy to mix, but since we sometimes separate it out into smaller batches to color I wait until it is done and then let the kids knead the color (powder or paste) into the dough, which is a fun activity in and of itself. Until everything homogenizes you get a pretty marbled effect. I have used wilton cake icing dye in the past (I keep it handy for dying wool) but this time we used powdered food coloring which I have no idea when or how I aquired. I assume it is ancient and not good for eating (does eating anything that brightly artificial ever seem like a good idea?) but very efficient at coloring paste, dough, wool, etc. I keep kool-aid packets around for wool dying as well, (maybe we post about that one day) and suspect they would work for play dough, but the fruity smell can be a bit overwhelming even with wool that has been rinsed repeatedly so I would use a very very small amount to start.