Home made playdough please!?

[babyonboard]

Any ideas for a recipe that actually works? And where to find natural food colourants to dye it with?

Cooked Playdough (flour and salt)
3 cups flour
1.5 cups salt
6 tsp cream of tarter
3 tbsp oil
3 cups water
Pour all ingredients into a large pot. Stir constantly over medium heat until a ball forms by pulling away from the sides. Knead the playdough until the texture matches playdough (1-2 minutes).

Store in plastic container. Should last for at least 3 months.

Tescos has "natural" food colourings. THey're more expensive than artificial ones and, given that you're not planning on the dough being eaten, why bother with naural ones?