In a stand mixer fitted with the dough hook, combine the flour, cornmeal, yeast, sugar, and salt. Mix on low speed until well blended. Add the water and melted butter. Continue mixing for 1 to 2 minutes until combined. Scrape down the sides of the bowl, then mix again. Increase speed to medium and knead until the dough is smooth and shiny and pulls away from the sides, about 4 to 5 minutes.

Coat a large bowl with 1 teaspoon of olive oil. Transfer the dough to the bowl and turn to coat. Cover with plastic wrap and let rest at room temperature until nearly doubled in size, about 1 hour.

While the dough rises, prepare the sauce. In a medium saucepan over medium heat, combine 1 tablespoon olive oil and 1 tablespoon butter. Add the minced onion, crushed red pepper, Italian seasoning, salt, and pepper. Cook, stirring frequently, until the onion softens, about 5 minutes. Add the garlic and cook until fragrant, about 30 seconds. Stir in the crushed tomatoes and sugar. Bring to a simmer, then reduce heat to medium-low. Cook, stirring often, until the sauce reduces to about 2 1/2 cups, about 30 minutes. Remove from heat, stir in the fresh basil and remaining 1 tablespoon olive oil. Adjust salt to taste. Cover and set aside.

Adjust the oven rack to the lowest position and preheat the oven to 425°F. Turn the dough out onto a clean countertop. Roll the dough into a 15 by 12-inch rectangle. Using an offset spatula, spread the softened butter over the dough, leaving a 1/2-inch border along the edges. Starting at the short end, tightly roll the dough into a cylinder. With the seam-side down, flatten the dough into an 18 by 4-inch rectangle. Cut the rectangle in half crosswise. Working with one half at a time, fold the dough into thirds like a business letter. Pinch the seams together to form a ball. Repeat with the remaining half. Transfer both balls to the oiled bowl, cover tightly with plastic wrap, and let rise in the refrigerator until nearly doubled, 45 to 50 minutes.

While the dough chills, cook the Italian sausage in a large non-stick skillet over medium heat, breaking it into chunks. Cook until browned and cooked through. Drain well and set aside.

Coat two 9-inch cast iron skillets or cake pans with 1 1/2 tablespoons of olive oil each.

On a clean countertop, roll one dough ball into a 13-inch round disk, about 1/4-inch thick. Loosely roll the dough around the rolling pin and transfer to one prepared skillet. Unroll and press the dough into the pan, working it into the corners and about 1 inch up the sides. If the dough resists, let it rest for 5 minutes before trying again. Repeat with the remaining dough ball and the second skillet.

Sprinkle each pizza with 2 cups of the shredded mozzarella. Divide the sauce between the two pizzas, spreading with the back of a spoon to cover the cheese. Top each pizza with half the cooked Italian sausage, then the olives, and finally the Parmesan cheese.

Bake until the crust is golden brown, about 20 to 30 minutes. If the top browns too quickly, tent with foil. Let the pizzas cool in the pans for 10 minutes before serving.