Anyone have a good source for learning how?

You might want to check with Risque Business ....she has done some gorgeous cocoa painting!

we just did cocoa painting in my pastry 2 class. we weren't given much instruction. she said you just add veg oil to cocoa powder and paint. one of the pamphlets she gave us said to paint from dark to light. i drew my design in pencil then flipped it over and traced the outline again and the pencil marks came out on the pastillage.