You can always try the Jessica Seinfield's Brown Recipe from her book Deceptively Delicious. These are healthy brownies that kids love. Just remember "don't serve them warm because it isn't until they are completely cool that the spinach flavor totally disappears". I haven't tried them yet but will someday. Here is a copy of the note on the right side of this webpage.
These are the HEALTHY brownies from Jessica Seinfeld's new book, Deceptively Delicious. She made them on Oprah last week and they looked great. The only change here is I made them with a mixture of wheat & white flour instead of oat flour and I used butter instead of trans fat free margarine as the original recipe calls for because that's what I have in my kitchen! To puree veggies, I used microwave then ran through the food processer. I would guess about 1 1/4 cups of carrots made the 1/2 cup puree and almost a whole bag of pre-washed baby spinach for the spinach puree. They are not overly sweet OR chocolatey but for being healthy, they are not bad! My 11 year old just came in and said YUM, BROWNIES!
Recipe:
http://www.food.com/recipe/jessica-seinfeld-healthy-brown...
Plus you can use jarred baby food instead of doing the veggies yourself. Here is message on that.
http://www.oprah.com/food/QandA-with-Jessica-Seinfeld-Can...
Good luck! Hope it works out for you.