Pre-heat the oven to 350 degrees F. Prepare brownie mix as directed on the box or use your favorite homemade recipe.
After the brownies are baked, remove the pan from the oven and set the oven to broil at 500-550 degrees F.
Allow the brownies to cool for a minute, then sprinkle marshmallows over the entire surface. Sprinkle the graham crackers on top of the marshmallows. Set the pan in the oven about 4-5 inches from the heat source, and broil for 30 seconds, or until the marshmallows are golden brown. Watch the pan very carefully so it doesn’t burn. Top the brownies with pieces of the chocolate bar. Allow the chocolate to set before cutting the brownies.