I will be doing an action figure cake this weekend and the birthday kid would like chocolate on chocolate. My question is the primary colors are grey and red, can I color chocolate bc frosting to get these colors? I don't see how, but I will bow to the wise ones of CC.
BTW: I will be adding fudge to buttercream for the chocolate frosting.

Lin, I don't think so. I would frost in chocolate then do the decorating in the appropriate colors made from white buttercream.