After you have baked your favorite cupcake recipe, allow them to cool and then fill up a pastry bag (fitted with a round tip) with white frosting. Pipe small looking clouds all over the cupcake. Pile it up high so it looks like a big fluffy cloud.
Next, cut an Airhead into 3 strips and place it on top of the clouds in an arching rainbow shape.
For the final touch, add sprinkles to each end of the arch.