Place a pizza stone in the oven and heat to 450 F. On a surface lightly dusted with semolina flour, punch the pizza dough down into a small disk and roll it into a 12- to 14-inch circle. Transfer the dough to a pizza peel dusted with semolina flour.
Transfer the dough to a hot pizza stone for 1 minute to parcook the crust. Remove the dough from the oven and transfer to a cooling rack.
Meanwhile, in a medium sauté pan, bring 2 teaspoons olive oil to medium-high heat. Use your fingers to pinch 4 ounces L&B Italian sausage into roughly 1-inch pieces and place them in the hot pan. Let the sausage get crispy on all sides by turning the pieces about every 30 seconds. Transfer the cooked sausage to a paper towel-lined plate.
In a circular motion, starting from the center, spread 4 ounces of your favorite pizza sauce on the crust and add thin layers of 3 ounces shredded fontina cheese and 3 ounces shredded mozzarella cheese. Evenly spread the cooked sausage over the cheese, then top with ½ yellow onion, julienned, and 2 ounces sliced pepperoni. Sprinkle the pizza with another 1 ounce of fontina and 1 ounce of mozzarella cheese.
Transfer the pizza to the stone and cook for 7 to 10 minutes, until the cheese is bubbling and beginning to brown. Remove pizza from the oven and drizzle evenly with pesto.