Penguin Cupcakes this summer since we don't have Oreos in Russia. Can do some kind of ice theme with the kids playing outside with colored ice cubes and ice eggs with toys inside, and a penguin cupcake for a snack since penguins like the cold ice.
"Rainbow Cupcake Frosting" Could be done on rainbow cupcakes. This looks yummy as well as pretty. I'm not a big fan of sweets, and I have little to no fondness for chocolate cupcakes, but I totally want to eat that.