Here is Addy's My Little Pony Rainbow cake. It was definitely a fun cake to make!
As you can see she was pretty excited too!
Originally I wanted to do a two tiered cake like this test cake I did below. But after icing it and it just didn't look pretty I decided to do the bottom in Rice Krispie Treats so it wasn't nearly as tall and just do a big one layer of cake.
So I made a double batch of Rice Krispie Treats and pressed them into a greased cake pan, not sure of the size, 12" maybe? Then let it set. It fit perfectly in my cake carrier so I stored it in there.
Then I colored my three layers of cake, one red, one yellow and one blue. I used the wilton color gels like the picture below. They work so much better than the liquid, they give really bright colors and I use them for all my coloring of icing and cakes and cookies.
1. Red cake on bottom
2. Layer of orange icing
3. Yellow cake
4. Green icing
5. Blue cake
6. Purple icing
Then I covered the whole cake with a thin "crumb coat" of white icing. You don't want the icing to be too thick if you're using fondant or it won't be smooth when you're done. You'll just be pushing around a lot of icing underneath and it will be bumpy.
I offset the cake to one side on top of the rice krispies. You could cover the rice krispies with fondant too but i thought I liked the little puffs like clouds I made here. After a while I started to smooth some of them out.
I used a big round tip to make these little puffs of clouds all the way around the cake and rice krispie bottom.
I was devastated but oh well, it still worked out pretty cute and no one even knew.
So as you can see it's not totally smooth and perfect but I worked all day on it. Literally until people started showing up.