• Preheat oven to 350 degrees F. Line a 9x13 inch baking pan with parchment paper. If you don't have parchment paper you can line it with foil and grease the foil.
• Prepare crust. Combine the graham cracker crumbs, sugar, salt and melted butter in a mixing bowl. Stir until moistened, then transfer the crumb mixture to the lined baking pan and press evenly over the bottom of the pan. Put in the refrigerator to set.
• Prepare brownie layer: Combine the bittersweet chocolate and butter in a microwave-safe glass bowl and heat on high, stirring every 30 seconds, until melted and smooth.
• With a hand-held electric mixer on medium-high speed, beat together the eggs and sugar in a large bowl until well blended. Reduce the speed to medium and gradually add the melted chocolate mixture to the egg mixture; beat until the mixture is smooth, scraping down the side of the bowl occasionally.
• Stir in the salt and vanilla, then stir in the flour. Scrape the brownie mixture into the crust-lined baking pan; smooth the top level with a rubber spatula.
• Bake for 30 minutes or until the top is smooth and the center is set when gently pressed with fingertip. At this point you can let it cool, or you can go ahead and just spread the marshmallow cream on top while slightly warm.
• Whisk together the marshmallow cream and the milk in a small bowl until the mixture is well blended and smooth.
• Pour the marshmallow topping mixture over the brownie layer in the pan. Spread or tilt the pan to level the topping and cover the brownie layer completely.
• Sprinkle the mini chocolate kisses evenly over the marshmallow topping. Then scatter the crumbled graham crackers all over the top.
• Bake in 350° oven for 3 minutes or until the chocolate kisses are glossy and the marshmallow topping is set. Let cool in the pan on a wire rack. Cut into bars.

Less Gooey Version

• Instead of putting the Hershey's pieces or chocolate on the top immediately, just put the marshmallow cream on top and let the bars cool. Chill until firm, then trim edges and slice into neat squares.
• Sprinkle crushed graham crackers over the top and decorate with pieces of Hershey Bar. Serve room temperature, or warm in the oven before serving OR with a pastry torch.