Combine Sugar, Peanut Butter, and Light Karo Syrup in a pan over low-medium heat.
Stir until the mixture in combined and just starts to bubble. Remove from heat.
Mix in Rice Krispies.
Pour into a 13 x 9 pan.
Melt Semi-sweet and Butterscotch Chips in the microwave in 30 second increments, mixing with a spatula between each time. This should take no longer than 2 minutes total.
Pour over Rice Krispies mixture. Let cool for an hour or so (or do a quick cool in the fridge), then loosen the Scotcheroos out of the pan and cut into squares.