Next, make the brownies. Start by creating a double boiler and adding the chocolate and cubed butter to the bowl. Melt the chocolate and butter together, stirring occasionally. While they are melting preheat the oven to 350 degrees F.
Fold in the remaining butterscotch chips and marshmallows. Pour it all over the pretzel crust and bake for 30-40 minutes, or until it passes the toothpick test. Allow to cool before cutting and serving