I found this on Amazon about the product...
The toy comes with everything your child needs to mix, bake, and decorate the cupcakes: a tiny mixing bowl, measuring spoon, water dropper, and miniature spatula for mixing the batter and frosting; a microwaveable container for baking the cupcakes; and a cupcake frosting gadget with a shape reminiscent of a KitchenAid standing mixer. And everything your little chef needs to get started is packaged in chic, girl-pleasing, contemporary pastels.
Mix It Up
Simply mix the cake mix with water using the provided measuring spoons and water dropper to reach the desired consistency (we found that a pudding-like consistency gives the best results), pour the batter into the cupcake paper, and put it in the plastic "baking dish," bake it in the microwave for about 30 seconds, and--voila!--out comes a completely baked cupcake. Because the cupcakes get pretty hot, an adult should handle them until they're cool enough to handle.
In the meantime, the frosting can be mixed up in the same manner. Again, it took us a few tries to get the proper consistency: it's especially important for the frosting to be, as suggested, the consistency of firm cookie dough to work properly with the cupcake froster.
Time to Decorate
The cupcake froster comes with a frosting tube with a plunger and decorator-type tip. Scoop the frosting into the tube with the miniature spatula and place it in the machine. (This step can prove almost impossible if the frosting is too runny.) Place the cooled cupcake below and push down the lever. The frosting machine simultaneously spins the cupcake and pushes out the frosting to create a spiral shape. Kids can put the finishing touches on with the included sprinkles or, as the "shortcut" cards suggest, with cut-up fruit or candy (you'll want to stock up on these beforehand). The finished cupcake is smaller than a regular cupcake and a bit larger than your standard mini cupcake.
So my take on this is if you want your kid to be able to do the whole thing on their own you will need an add water only type cake mix, maybe the betty crocker single serve microwave mixes would make enough batter for the 4 cupcakes. Atleast you can find coupons for these. Similarly with the frosting I think you could substite any "make from a powder" type frosting but it seems that a can of frosting, premixed would probably be too runny...