In a large mixing bowl combine sugar, flour, cocoa powder, and salt. Stir well. Then whisk in melted butter, eggs, and vanilla extract. Gently fold in 1 1/2 cups Golden Grahams and 1 1/2 cups white chocolate chips.
Spread the brownie batter in the prepared baking dish. Bake for 40 minutes. Then pull out of the oven and sprinkle with 2 cups Golden Grahams, 2 cups mini marshmallows, and 3/4 cup chocolate chips.
Place back in the oven and bake another 5-10 minutes, until the marshmallows are toasted. (Watch them closely so they don't burn!)
Cool the brownies for at least 15 minutes before trying to cut. Cut into 24-30 pieces and serve!