I've seen a couple of variations of the Rainbow Cake around and I've wanted to try to make it ever since I saw it on the Martha Stewart show a couple of months ago. Recently, however I found another version on the Not Quite Nigella website and decided to try to make it for my sister's birthday, which was yesterday. I decided to go with NQN's version over Martha's, as it had the curve like an actual rainbow and didn't involve making separate cakes. I actually expected this to be one most difficult cakes I've made, although in the end it wasn't too hard. Also sorry in advance for some of the photos being a bit blurry. I had to use my iPhone, because my camera's playing up.