Step 1: Put butter and peanut butter chips in a big pot. Heat them on medium heat until they melt and become smooth.
Next, put condensed milk, vanilla extract, and marshmallows into the melted butter and peanut butter mixture. Mix until everything is smooth and well combined.
Step 3: Apply butter or non-stick spray to a rectangular baking dish that measures 9 by 13 inches. Put half of the peanuts on the baking dish.
Step 4: Pour the mixture from step 2 evenly over the peanuts, and then sprinkle the rest of the peanuts on top.
Step 5: Put in the fridge or leave at room temperature until it becomes firm. Cut the candy into bars and enjoy them.