Stir together the sugar and corn syrup in a large saucepan. Cook over medium heat, stirring frequently, just until the mixture comes to a low boil and the sugar has dissolved. Don’t over-cook, or the bars will harden.
Remove from the heat, and immediately stir in the peanut butter and salt. Pour over the cereal, and stir to combine.
Use a rubber spatula coated with cooking spray to press the mixture evenly into the prepared pan.
Place the chocolate chips and butterscotch chips in a microwave-safe bowl. Heat at half power in 30-second increments until the chips melt when stirred. Stir until smooth, and then spread evenly over the bars.
Cool completely before cutting into bars.
Notes
Store in an airtight container at room temperature up to 5 days.