I made this rainbow cake for my daughter’s 8th birthday. She had a very generic unicorn theme with pastel colors and rainbows. I searched for and found the general idea for this cake online (I can’t remember where I saw it). I am all about making homemade cakes that are pretty but fairly easy and this one looked easy enough to do.
The cake is a purchased boxed cake made in a 9×13 glass pan. I iced the cake using canned white icing. I purchased Jelly Belly jelly beans by the color in pink, orange, yellow, blue and purple to make the rainbow, lined them up and used mini marshmallows to make the clouds. I had to pile on the marshmallows and stick some of them together with dabs of icing to keep them piled high.
I kept the cake in the clear 9×13 pan and piped the purple words and stars around the border. The kids loved the cake and the jelly beans were especially fun and tasty to eat. Easy and fun!