Hi, I live in South Africa where we don't get all the lovely ingredients available in bigger countries. I want to decorate a cake for a competition with a pencil sketch type picture on top. I have thought of using cocoa butter but I would like something I can do finer work with. Any ideas?

Sorry, not sure what you're trying to describe doing? What do you mean by sketch type picture?

Something similar to cocoa butter painting, but I would like fine lines like a pencil sketch on paper would look

Very thin paint brush and black food coloring?