All you do is use 2 white cake mixes and oh....5 cans of icing! You could probably use less icing :) Divide the batter into 6 bowls and add food coloring to get all the colors of the rainbow.
Then pour into cake pans and bake.
Put icing between each layer and if it's leaning at all (like mine was) put a few skewers in it to keep it from sliding.
Then, put the cake in the refrigerator while you go to the store to get more icing. Haha.
Ice the outside and decorate however you want. I saw one online decorated with skittles in the shape of a rainbow with mini marshmallows for clouds. I decided on rainbow sprinkles because I love sprinkles! I left a skewer in the middle and out a flag on it that said happy birthday Garrett.
We took Garrett and Gage out to dinner to celebrate! Zach had a great time.
I wish I could have videoed the boys' reactions to seeing the rainbow inside. It was classic. So sweet. It was so worth making this for Garrett. I don't think anyone would have appreciated it more :) We gave him a couple automatic nerf guns that were really cool.
I love these boys so much!!!