This recipe was given to me by my friend, Sara. I just tried it and it's awesome! Note that you can use several combinations of fruit and soda (Sara used blueberries and 7-up) but I'll write what I did. You could even combine different fruits... Be as creative as you want!
16 oz. frozen peaches
1 yellow cake mix
1 can Diet Cream Soda
Preheat oven to 325. In a square baking dish, layer fruit, then cake mix (dry). Pour soda evenly over the top. (No need to even stir!) Cover and bake 20 minutes, then uncover and bake another 40 minutes.
Voila! Super easy!! :)