Preheat pizza stone for 10-15 minutes on medium high heat.
You can test that the stone is ready by using a drop of water over the stone the water should evaporate immediately.
While the stone is heating, prepare the pizza dough as directed on the packaging and place on a pizza peel dusted with cornmeal (or flour).
Spread the Nutella over the pizza dough leaving a ¼ - ½ inch border around the edge of the pizza dough.
Sprinkle approximately ½ cup of the graham crackers over the Nutella followed by the marshmallows and chocolate chips.
Decrease the heat on the grill to low (approximately 200-250F).
Sprinkle the top of the pizza stone with cornmeal and transfer the pizza to the stone with a pizza peel. Close the lid on the grill.
After 5 minutes, open the grill cover and rotate the pizza to allow for even cooking.
Close the lid and cook for approximately 5-7 more minutes until the marshmallows and pizza crust are golden brown.
Top immediately with remaining chocolate chips and graham crackers.
You can also drizzle with chocolate sauce.
