Since my theme is Super Mario, I chose to do a goomba for my chocolate piece.
Here he is before chocolating (my printer is running out of ink). He's all reversed and taped down
I ran out of time before I could finish the white bit but here's most of it traced in chocolate.
Keep in mind that what you're seeing will be covered up by a block of chocolate and the part that's actually facing the plastic will be the end result.
It's going to be a fun piece I think. I am excited to see it done. :-)