My friend is having birthday, and I want to make her a cake.

I want it to just be a simple 9 inch round cake, and I wanted to do a FBCT on the top.

One problem I'm having is that the design I want to use has a bunch of black in it. And I don't have black coloring, and can't get any before I want to give her the cake. But I do have chocolate.

I was hoping perhaps I could melt the chocolate and use that for the black outlines, and to fill in the black section of the design, and then use butter cream for the rest like normal.

Would this work? Or would they not work together?