I found a new recipe online that I tried today: Chocolate Peanut Butter Cheesecake Brownies!
Preheat oven to 350 degrees.
Grease a 9x13-inch cake pan.
Prepare one box of brownie mix (9x13-inch pan size) according to package directions. Spread mixture into pan.
Using a mixer, blend together 8-ounces of cream cheese (room temperature), 1/3 cup of peanut butter, 2 eggs, and 2 cups of powdered sugar. Once blended well, spread on top of brownie mixture. Using a knife, cut through the batter a few times to marbelize.
Sprinkle 1/2 cup of semi-sweet chocolate chips on top.
Bake for 45-50 minutes.
Store covered in refridgerator.