Position a rack in the center of the oven and preheat to 400 degrees F. Lightly sprinkle a heavy nonstick baking sheet with cornmeal. Set aside.
In the bowl of the food processor, add the artichoke hearts, Pecorino Romano, ricotta, fontina, sun-dried tomatoes, lemon juice, salt, pepper and lemon zest. Pulse until combined and chunky.
Using a knife, cut the pizza dough into quarters. On a lightly floured surface, roll out the dough into four 6-inch circles, each about 1/4-inch thick. Using a pastry brush, brush the dough with the egg white. Place a quarter of the filling on one side of each circle of dough. Fold the dough over the filling, forming a half circle. Pinch the edges of dough firmly together and crimp to seal. Place the prepared individual calzone on the prepared baking sheet.
Drizzle the calzones with extra-virgin olive oil. Sprinkle lightly with salt and pepper. Using a sharp knife, cut a slit on the top of each calzone. Bake until golden brown and the filling is bubbling, 30 to 35 minutes. Serve alongside warmed tomato-basil sauce.
Recipe courtesy of Giada De Laurentiis