louisiana cupcake
When one party lies flat on their stomach and a Styrofoam cup is placed between their thighs by a second party, and the first party proceeds to defecate directly into the cup, the resulting product is called a Louisiana cupcake, due to the resemblance to chocolate frosting.
I was helping my girlfriend shave her ass last night, and she shat into the cup I had shaving cream in! Bitch gave me a Louisiana cupcake!