In a medium microwave-safe bowl, microwave the chocolate and butterscotch chips at 30 seconds intervals, stirring between each one, until fully melted. Spread the mixture over the rice krispie mixture in the pan.
You can store this no-bake treat in an airtight container at room temperature to enjoy for up to 4 days. Any longer than 4 days, and they start to lose their chewy texture. They can also be stored in the refrigerator if you prefer.