Chicago (Pizza)

This sign went up a week or so ago, and every time I saw it I thought of pizza. It's opening night (I have tickets to tomorrow night's show; I'm looking forward to seeing what's on sale at the concession stand), and I finally gave in to my craving. Here is the recipe, adapted from this one in Cook's Illustrated:

Chicago-Style Deep Dish Pizza with Spinach and Ricotta
Serves 4

For the dough:

1 1/2 cups unbleached all-purpose flour
1/4 cup yellow cornmeal
3/4 teaspoon salt
1 teaspoon sugar
1 teaspoon instant yeast
1/2 cup plus 2 tablespoon room temperature water
1 1/2 tablespoons unsalted butter, melted, plus 2 tablespoons softened

For the filling:
1 tablespoon extra-virgin olive oil
1 shallot, finely chopped
1 garlic clove, finely chopped
1/4 teaspoon dried oregano
Salt
One 14.5-oz. can diced tomatoes
8 ounces shredded mozzarella cheese
1/3 cup ricotta cheese
One half of a 10-ounce package chopped frozen spinach, thawed and squeezed dry (this turns out to be about 1/4 cup--you will be amazed at how much water you can get out of it if you try)
1/4 cup grated Parmesan cheese

1. Make the dough: Combine the flour, cornmeal, salt, sugar, and yeast in the bowl of an electric mixer fitted with a dough hook (or in a large bowl, if you want to knead by hand). Pour in the water and the melted butter and mix with a rubber spatula until a rough dough forms. Knead on medium with the dough hook until the dough comes together in a smooth ball, about 5 to 7 minutes (alternatively, turn the rough dough out onto a lightly floured countertop and knead by hand until the dough comes together, 7 to 10 minutes). Place in an oiled bowl, cover the bowl with plastic wrap, and let the dough rise until doubled or tripled in volume, 1 1/2 to 3 hours.
2. Turn the dough out onto a lightly floured countertop and use a lightly floured rolling pin to roll it into a 15-inch by 6-inch rectangle. Dot the dough with 2 tablespoons softened butter and spread it evenly over the dough with an offset spatula. Starting at the short end, roll the dough into a tight cylinder. Place it seam side down on the counter top and roll the cylinder into a 9-inch by 4-inch rectangle. Starting again at the short end, fold it into thirds, as you would a letter, and pinch the seams together with your fingertips. Lightly shape the dough into a ball, put it back in the oiled bowl, cover again with plastic wrap, and refrigerate for at least 1 hour and up to 6 hours.
3. Preheat the oven to 425 degrees. Heat 1 tablespoon olive oil in a large saucepan over medium-high heat. Add the onion and cook until softened, about 3 minutes. Add the garlic and cook until fragrant, about 30 seconds. Stir in the tomatoes and oregano, bring to a simmer, and cook until the tomatoes are breaking down and the sauce is thickened, about 20 minutes. Remove from heat and season with salt. Let cool to warm room temperature.
4. Spray a 9-inch round cake pan with nonstick cooking spray. On a lightly floured surface, roll the dough into a 13-inch round. Transfer it to the pan, pressing it into the bottom and up the sides. Sprinkle the mozzarella over the dough. Spoon the sauce on top of the mozzarella. In a small bowl, combine the ricotta, spinach, and 1/4 teaspoon salt. Dot the top of the pizza with spoonfuls of the ricotta and spinach mixture. Sprinkle with Parmesan.
5. Bake the pizza until the crust is browned and the cheese is bubbling, 25 to 30 minutes. Transfer to a wire rack to cool for 10 minutes before slicing and serving.