Baking, The Art You Can Eat!

My daughter is now 5!!! Woooo! For such a big milestone of all of us surviving these past five years, I wanted to make sure she got a pretty big "WOW" from her cake! Her theme this year was My Little Pony, which was a very spur of the moment obsession for her that really came flying out of nowhere.... Thankfully, she had a ton of MLP hand-me-down toys and it's still pretty popular in party & toy stores - had MLP balloons, plates, napkins, banners, and plenty of stuffed ponies (added plenty of blue since that's her favorite color and helps balance out the crazy amount of pink).  Anyways, on to the cake!  So the idea for the cake was make a normal cake but drown it in rainbows. That means the inside has to have rainbows and the outside has to have rainbows!  Because I didn't realize I was going backwards, the bottom layer started as red (rather pink in the picture - strawberry flavored!) and it would go up from there - red, orange, yellow, green, blu