Line a 9”x9” square baking pan with tin foil and spray lightly with cooking spray (or grease with butter).

Stir the crispy rice cereal and salted peanuts together in a large heat-proof bowl (e.g., glass or stainless steel). Set aside.

In medium-sized, heavy-bottomed saucepan placed over low heat, combine the peanut butter, corn syrup, brown sugar, and butter. Stir until mixture is blended and heated. Do not boil.

Remove saucepan from heat and pour mixture over the cereal and peanut mixture. Stir to mix. Press mixture into prepared baking pan.

For topping, melt the chocolate in a microwave-safe bowl, a few seconds at a time. When chocolate is about half melted, stir in the peanut butter and butter. Continue to microwave in short bursts of seconds until chocolate is melted. Pour the topping over the square in pan and smooth with a knife or small flat metal spatula. Let cool completely to room temperature before lifting square from pan and cutting it into squares or bars of desired size. Square may cut out better if cooled square has been placed in the refrigerator for 15-20 minutes.