Challenge Upside Down Turtle Cake

My son always challenges me for his birthday cake, each year he asks me to make him something he thinks I cannot do. So far I have succeeded! This year he asked for a upside down turtle cake.

I told him there was no way I could do that, he laughed and said he finally got me!! Well he didn’t, I did it and it was pretty cool, I surprised him and he was very excited!