Preheat oven to 350 degrees F. Prepare the brownie mix according to package instructions. Add foil or parchment paper in a 13 x9 baking dish making sure to leave extra to hang over the sides (makes it much easier to remove the bars!) Grease the parchment or foil with non-stick cooking spray.  Add your brownie mix to the baking dish. Top with your Oreo cookie chunks. Crumble your cookie dough and cover the top completely. Bake for 30-35 minutes. Let cool before cutting into bars.