I let the base sit for about 15-20 minutes to cool slightly while I make the topping. In a medium microwave-safe bowl, I combine the chocolate chips and butterscotch chips. I microwave them in 30-second bursts, stirring well after each, until they are completely melted and smooth. Alternatively, you can melt them together in a small saucepan over very low heat. I then pour this melted chip mixture over the slightly cooled cereal base. Using an offset spatula or the back of a spoon, I quickly spread it into a smooth, even layer that covers the entire surface. I let the pan sit at room temperature until the topping is completely set, which takes about 1-2 hours.
Pro Tips for Best Results
The type of peanut butter is non-negotiable. I tested this with natural peanut butter (the kind that separates), and the bars were oily, didn’t bind properly, and were a crumbly mess. Conventional, shelf-stable creamy peanut butter has the right emulsifiers and consistency to create that perfect, chewy, binding “glue” that holds the Scotcheroos together. Trust me on this one—it makes a huge difference.
Press, press, press! When transferring the cereal mixture to the pan, don’t just spread it. Use a sheet of parchment on top and really lean into it with the palms of your hands or the bottom of a flat measuring cup. A firmly packed base is the difference between a Scotcheroo you can pick up and a pile of peanut butter cereal. This ensures clean cuts and the right dense, crunchy-chewy texture.
For the topping, don’t overheat the chips. Chocolate and butterscotch chips can scorch or seize if zapped for too long. The low-and-slow method (30-second bursts with stirring) is foolproof. If the mixture seems thick, you can stir in a teaspoon of vegetable oil to make it more fluid for easier spreading.
Common Mistakes to Avoid
The most common mistake is letting the sugar-corn syrup mixture come to a rolling boil. If you boil it, it will become too hard when it cools, resulting in bars that are jaw-breakingly tough instead of delightfully chewy. My first batch was like peanut brittle with cereal in it because I got distracted. Don’t do what I did! Heat it just until the sugar dissolves and it starts to bubble at the edges, then immediately remove it from the heat.(See the next page below to continue…)