I have made these many times and they are some of our family's favorites! I use 1 bag of both chocolate chips and butterscotch chips, and also add a tsp of vanilla when adding peanut butter!
This is the closest version of the recipe I use that I could find on this site. The only change is that I use 1 cup of milk chocolate chips and 1 cup of butterscotch chips as I don't like the chocolate topping too thick. My family's FAVORITE treat since the 70's!