Line two baking sheets with wax paper or parchment paper. If you aren't planning to put the pans in the refrigerator to help the haystacks set more quickly, then you can simply lay a large sheet of paper on your countertop.
Place the butterscotch chips and peanut butter in a large microwave-safe bowl. Heat at half power in 30-second increments until the butterscotch melts when stirred. Or if you prefer, melt in a double boiler. Stir until smooth and thoroughly combined.
Gently fold in the noodles and peanuts until evenly coated.
Drop the mixture by 2-3 teaspoon portions onto the prepared pans. If necessary, use a spoon to shape them into clusters or “haystacks.”
Cool on the pans for about 2 hours or refrigerate until set and firm.
Notes
*You can use salted or unsalted peanuts. If yours are unsalted, you may want to add a pinch of salt to the mixture.
Store in an airtight container at room temperature up to a week.