After a lot of time and a LOT of swearing, this was the result:
Not perfect, but a good jumping off point. The best part was the taste. Oh heavens....devilishly good. Four layers of dense chocolate cake with peanut butter and milk chocolate chips, filled with creamy peanut butter straight up, then frosted with my favorite semisweet chocolate buttercream, and the piped peacock is in a whipped peanut butter frosting.
Pass the milk, please.