Sourdough NY Pizzas with Dill Mushrooms

Steps

1. Day 1, about 8 a.m.: feed your sourdough starter with its usual feeding (not part of this recipe's amounts) and leave it at about 75°F (24°C) for 4 to 6 hours, until doubled, domed and bubbly.
2. When the starter peaks, stir the sourdough starter into the water in a large bowl, then add the bread flour and mix until no dry bits of bread flour remain. Cover and rest 30 minutes.
3. Add 11 g of the salt (most of the salt) and 15 g of the olive oil (half of the olive oil) to the dough and squeeze and fold until fully absorbed, about 3 minutes. Counting the starter, the dough is about 65% hydration and 2% salt.
4. Bulk rise covered at about 75°F (24°C) for 4 to 5 hours. During the first 90 minutes, do 3 sets of stretch-and-folds 30 minutes apart. Bulk is done when the dough has grown about 50%, looks smooth and shows bubbles on the sides.
5. Divide the dough into 2 equal pieces and shape each into a tight ball. Place in lightly oiled, covered containers and refrigerate 24 to 48 hours for the overnight cold proof, which builds tang and a chewy NY-style crust.
6. Day 2 or 3: take the dough balls out 2 to 3 hours before baking and let them warm at about 75°F (24°C) until puffy and the dough springs back slowly when poked.
7. Make the sauce: blend or crush the canned tomatoes with the tomato paste, half of the garlic, the oregano and the remaining 2 g of salt. Set aside uncooked.
8. Place a pizza steel or stone on the top-middle rack and preheat the oven to 550°F (288°C) for 45 to 60 minutes.
9. Meanwhile, toss the mushrooms, red onion and the remaining half of the garlic with 10 g of the olive oil (two-thirds of the remaining oil) and roast on a sheet pan in the hot oven for 8 to 10 minutes, until browned and dry. Stir in half of the dill.
10. Dust a peel with half of the semolina. Stretch one dough ball by hand into a 14-inch round, leaving a thin rim, and lay it on the peel.
11. Spread half of the sauce over the dough, then scatter half of the mozzarella, half of the mushroom mixture and half of the parmesan.
12. Slide onto the steel and bake 8 to 10 minutes, until the crust is deep golden, the underside is crisp and the crust reaches about 200°F (93°C) inside.
13. Repeat with the remaining semolina, dough ball, sauce, mozzarella, mushroom mixture and parmesan.
14. Finish both pizzas with the remaining half of the dill, the red pepper flakes and a drizzle of the last 5 g of olive oil. Cool on a rack 3 minutes so the crust stays crisp, then cut each pizza into 6 slices.