Melt butterscotch and peanut butter. In a small microwave-safe bowl, combine butterscotch chips and peanut butter. Microwave the mixture for 30 seconds at a time. Stir well in between each 30 seconds until it is smooth.
Add other ingredients. In a large bowl, combine peanuts and Chow Mein noodles. Pour the melted butterscotch mixture over them, gently stirring until everything is well coated.
Make piles on parchment paper. Drop the mixture onto parchment paper to form 2-2.5-inch piles. Let them cool until the butterscotch is fully hardened.