Prepare the brownie batter according to package directions. Place graham cracker shells on a baking sheet and fill with brownie batter.
Bake at 350* for 20-25 Minutes or until a toothpick inserted in the center comes out with moist crumbs. immediately sprinkle with marshmallows and chocolate chips. Bake 3-5 minutes longer or until marshmallow are puffed and golden brown.