Grease bottom and sides of 8x8 baking pan with softened butter.
In a large saucepan, melt butter over medium heat. Swirl the pan occasionally to prevent burning. After a couple minutes, the butter will begin to foam and turn from yellow to a deep golden brown and have a nutty aroma. (Some brown sediment will likely settle in the butter, and that's okay!)
5 tbsp. unsalted butter
Add marshmallows and stir constantly until completely melted. Remove from heat and add vanilla.
16 oz. mini marshmallows , 1 tsp. vanilla extract
Add cereal & pretzels. Stir with a rubber spatula until everything is mostly coated. Then add butterscotch chips and finish mixing everything until well coated. Gently press mixture into the bottom of 8x8 pan.
½ cup butterscotch chips, 5 cups crispy rice cereal, 1 cup crushed pretzels
Allow to cool completely before cutting into squares.
