Place the sugar and corn syrup in a medium sized sauce pan. Bring to a low boil and boil for 1-2 minutes, or until sugar is completely dissolved (don't over cook or your bars will be hard like candy--just long enough that the sugar is smooth and dissolved) . Remove the pan from the stove and stir in the peanut butter, salt and vanilla. Once the mixture is smooth, add the cereal and chopped peanuts (peanuts are optional--I love this with them because you then get the sweet and salt combo that I love so much!).
Spray a 9x13 pan with cooking spray and when the cereal/peanut butter mixture is combined, spread it evenly into the pan. Set aside or cool in the fridge while you make the topping.
In a microwave safe bowl, melt the milk and butterscotch chocolate chips until smooth (in the same dish). Once the chips are soft, stir them together and then spread the melted chocolate over the cereal bars. Garnish with extra chopped nuts and keep cool until ready to eat, or until chocolate top hardens. Cut into squares and serve.