If you aren't that into baking, here's a SUPER easy brownie recipe that came in the McDougall Newsletter. When I serve these brownies to people I wait until after they've tasted them (and gone back for seconds) to tell them about the pumpkin. You really can't taste it underneath the chocolate!
Preheat oven to 325 degrees. Pour the mix into a bowl, stir in the pumpkin and chocolate until very well combined. Pour into a 9 X 13 non-stick baking dish and bake until done, about 25 minutes (insert a toothpick into the center, if it comes out clean it is done).