In a large saucepan over low heat, melt peanut butter and butter. Add marshmallows; cook and stir until melted. Remove from the heat.
Stir in the cereal and peanuts; mix well. Spread onto a greased baking sheet. Cool. Break into bite-size pieces. Chill for at least 1 hour. Store in the refrigerator.
Every editorial product is independently selected, though we may be compensated or receive an affiliate commission if you buy something through our links. Ratings and prices are accurate and items are in stock as of time of publication.