Diet Cake
I have never tried it with a white or yellow cake. Someone told me they used 7-Up in a white cake mix and it was bland. I have only used diet Coke, Dr. Pepper and Diet Pepsi w/lime in a chocolate cake and it is fabulous!! I really watch the time it has been in the oven though and 5 mins. before the box says it's done I start checking it. The texture is wonderful, almost gooey! So good!