Preheat a pizza stone at 450 in the oven.
On a floured surface, roll out pizza dough very thin and stretch into a rectangle about 6 inches by 8 inches. Transfer to a pizza peel.
Spread the marinara across the dough. Sprinkle the cooked sausage, mushrooms and shredded mozzarella over the pizza dough. Tear the slices of mozzarella into roughly 1 inch sized pieces and sprinkle over pizza dough.
Sprinkle the preheated pizza stone with cornmeal, slide the pizza off of the peel and bake for 8-10 minutes until the edges of the dough begin to brown and the cheese begins to bubble.