What's the point?
Not sure how it can be called a rainbow mix when it literally includes nothing but the basic cake mix, but apparently that's fine advertising! Includes no sprinkles, no icing, nothing. The cake itself is just.... Meh. Nothing amazing. And DEFINITELY not worth the cost for just an ok sponge. You literally might as well just buy all the proper ingredients and make a mix yourself. It will cost about the same for more and for something much nicer.
Just yum and I cooked this in a cake liner put in slow cooker on high for 1 hr 30 minutes lovely