The deep dish pizza is Chicago’s most well known food, and learning how to make it can be quite simple.
Dissolve your sugar and yeast in warm water, and let the bowl stand for 10 minutes. Add 1 cup of flour and your salt to the yeast mixture, whisking until combined. Then add 1 ¾ cups of flour, stirring while you wait for a dough to form. Put the dough on a flour surface and knead until elastic. Keep adding flour to keep it from sticking to your hands. Put the dough in a sprayed-down bowl, coating in fully. Cover the dough and let it rise until doubled. Then punch it down and let it stand.
Preheat your oven to 375 F and warm up a large skillet to medium high heat. Oil your pan and add your sausage and onion, cooking for 5 minutes. Drain off any oil and set aside. Put your mushroom in the pan and cook for 5 more minutes, stirring regularly. Set these aside too, and add some olive oil and garlic to your pan. Let them brown and add your tomato paste, oregano, fennel and tomato sauce. Let this simmer for 5 minutes to allow the sauce to thicken. Coat your cast-iron skillet with ½ tsp. of olive oil and sprinkle in your cornmeal. Put your dough in the skillet, stretching it to cover the sides and bottom. Sprinkle your mozzarella over the dough and then top that with your sausage and mushroom mixtures. Then put your sauce in, and top that with your Parmesan. Bake for 40 minutes or until brown.