Heat oven to 350°F (325°F for dark or nonstick pan). Lightly spray 13x9-inch pan with CRISCO® Original No-Stick Cooking Spray.
In large bowl, stir dry brownie mix and graham cracker crumbs until well mixed; set aside.
Into medium microwavable bowl, squeeze peanut butter from peanut butter packet (from brownie mix). Add butter. Microwave uncovered on High 1 minute to 1 minute 30 seconds, stirring once, until butter is melted. Stir until smooth.
Pour peanut butter mixture over brownie mixture; stir until well mixed. Press evenly in pan.
In same medium microwavable bowl, mix milk, 1/3 cup peanut butter and 1/2 cup of the peanut butter chips. Microwave uncovered on High 1 minute, stirring once, until mixture is melted. Stir until smooth.
Gently pour milk mixture evenly over brownie layer in pan; spread evenly. Sprinkle remaining 3/4 cup peanut butter chips, the chocolate chips and peanuts over milk mixture; press in lightly.
Bake 18 to 22 minutes or until edges are golden brown and center is just set when lightly touched (do not overbake). Cool completely in pan on cooling rack, about 3 hours. For bars, cut into 6 rows by 4 rows.