Bake the cupcakes and let them cool.

While the cupcakes are cooling make your frosting of choice.

Cut the tip off of the pastry bag, add in an extra-large star piping tip to the bag. Using the paintbrush paint a line of each gel food coloring starting at the inside tip going halfway up the bag, making sure you are going in the color order of the rainbow.

Fill the bag with the buttercream. Pipe the buttercream in a swirl on each cupcake.

Cut the tip off the second pastry bag and add the straight piping tip. Fill the bag with buttercream. Pipe three small circles on the side of the cupcake and three small circles to the top of the cupcakes.

Cut the rainbow strips in half. Stick one side of the candy into each of the small dots of buttercream to create a rainbow shape.