A couple years ago I saw an article in a magazine (sorry can't remember) that made rainbow cupcakes with white icing for St. Patrick's Day. My kids call them pot of gold cupcakes.
Ever since I saw the article I've made these each year for my kiddos.
It's a really simple recipe, but a bit time consuming.
1 box white cake mix (not yellow)
3 egg whites (or whatever your box calls for - same with oil and water)
1/3 cup of vegetable oil
1 1/4 cup of water
container of white cake icing
gold wrapped chocolate coins (optional)
Make the cake batter according to the box. Once it's well mixed separate the batter equally into 6 separate containers.
Add food coloring to each separate container as follows:
red: 18 red drops
orange: 12 yellow and 4 red drops
yellow: 12 yellow drops
green: 12 green drops
blue: 12 blue drops
purple : 6 blue and 9 red drops
Mix the batter and food coloring up very well. It should create nice, bold colors.
Then bake according to the box. Icing and top with a gold chocolate coin.