I just tried my aqua mini donut maker.  I took a cake mix and added soda (instead of eggs and oil) and it made the batter really airy and the donuts soft and fluffy.  Would probably be denser if I made without the soda.  Took about a tablespoon of the mix for each donut, and filled higher than recipe book said because of the airiness of the batter.  Cooked about 4-5 minutes (did not flip them over).  Came out easily, just used a knife since I don't have any toothpicks.  Used some regular cake frosting and used that in the center and was so yummy!