I like to make a cake in the batter bowl, slice it in half (from top to bottom) and then put the big ends together to make an easter egg.
I just use a Duncan Hines (or whatever) cake mix and bake it in the batter bowl. It takes about an hour, though, so you have to keep your eye on it and check for doneness with a cake tester. I think I may have a pic of the one we did last Easter - you'll have to forgive the decorating - my kids did it.