Anyway, here is the final product. Each bag is over 5 cups of playdough.
And of course, you want the recipe, because I think it's so much fun to do.
I made a few changes. I added the food coloring after the dough was finished and used Kosher salt since I didn't have enough regular salt for even one batch. Since the water I used was hot and we were cooking it, I figured that chemically it didn't matter as it would dissolve. It takes just a few minutes for the dough to thicken. You'll want to take it out of the pan to cool as soon as it thickens or it will continue to cook and you may have a dryer dough.
For the color (this is mostly for my future reference), I used Wilton gel food coloring.
For Red: A lot of it. Probably half a container of the Christmas Red to get a vibrancy I liked ~1/4 ounce
Orange: 3 ml Orange
Yellow: 1ml Golden Yellow
Green: 2 ml Kelly Green
Blue: 3 ml Royal Blue
Purple: 2 ml violet + 3 ml Burgundy
My mom asked me if how much cheaper it was to make it vs. buying the same amount of PlayDoh. I figure it is at least 36 regular sized jars of PlayDoh which would cost about 36 dollars to make. Making it myself cost 12 cups of flour (~$5), 12 Tbsp of cooking oil (~$.50), 6 tsp of Cream of Tartar (~$2.00), 6 cups salt ($1), and the food coloring ($1.50 as I bought it at Michaels with a 50% off coupon and used very little other than the red) so $10, but really probably less as I overestimated on all these prices. If I make it for the girls, as I surely will, I'll be making a batch, separating it into 6 pieces and coloring them individually.