Heat oven to 350 degrees. Spray a 9×13 cake pan with non-stick spray.
In a small bowl combine the graham cracker crumbs, 6 tablespoons of melted butter, and 2 tablespoons of sugar. Mix and press into the bottom of your pan.
In another bowl combine the flour, salt, and baking powder. In the bowl of a stand mixer combine ¾ cup granulated sugar, ½ cup butter and beat until creamy. Add the egg and vanilla and mix until just combined. Slowly add in the flour mixture until well combined.
Gently spread the cookie dough on top of the graham cracker crust. Evenly sprinkle the chocolate chips and mini marshmallows over the cookie dough. Then pour the sweetened condensed milk over the top.
Bake for about 20 minutes. Let cool several hours before cutting.
Recipe by Reality Daydream at https://realitydaydream.com/smores-magic-bars/