Playdoh?

It seems like there's a way to do it, I just can't think straight on this one.

Get a can of water thickener from somplace that sells stuff for hospital patients. My grandfather was on asperation precautions. We had to add this powder to his fliuds to make it thick and easier to swallow. Dont know how long it will last for or if it goes bad. Im thinking like riteaid or walgreens. Cant hurt to try!!

hmm, flour/water then a couple drops of green dye...

I think I'm going to end up using Envirotex lite, a thick resin that dries clear and smooth, also has no odor. You can add colors to it as well.