If you are talking about the giant cupcake mold, I have a Wilton one. We love it and have used it many times, especially for first b-day smash cakes. One thing tho...just use a regular type cake mix for it. We have tried special cakes (like a banana cake from scratch) and it was far far too dense and just never cooked right. Mush in the middle.
We just buy flavored cake mixes if they want something different (like a strawberry cake or lemon or spice cake, etc). Cake mixes are lighter and cook better in it.
Ok now I re-read you need to do milk free. That must eliminate a commercial cake mix. Well just don't do any sort of dense cake..and do a practice round, even if you just throw it away. You don't want to be stuck with no cake! Then we always just did another batch (or whatever was needed) of regular size cupcakes for the guests. The big one was for pictures and for the 1 year old (or other young aged child) to smash for all of our parties! Watch the decorations too...remember they are just little, so no crunchy or choker small decorative elements (like colored candies, etc). Try to stick to fancy swirls and such with the frosting!
Have fun!