San Francisco Sourdough Loaf

Ingredients

• 100 g active sourdough starter, about 1/2 cup
• 375 g water, about 1 2/3 cups
• 500 g bread flour, about 4 cups
• 11 g fine sea salt, about 2 teaspoons
• rice flour, for dusting the banneton

Before you cook

• Feed the sourdough starter 8 hours ahead and use it when it has doubled and smells sharply sour.
• Line a round proofing basket or a bowl with a towel and dust it heavily with rice flour.
• Set out a Dutch oven with a lid.

Steps

1. Stir the starter into 350 grams of the water until the water turns cloudy.
2. Add the bread flour and mix by hand until no dry patches remain.
3. Cover the bowl and let the dough rest for 45 minutes so the flour hydrates.
4. Sprinkle the salt and the remaining 25 grams water over the dough and squeeze it through until fully worked in.
5. Let the dough rise at room temperature for 4 hours, folding one side over the center and rotating the bowl four times every 30 minutes for the first 2 hours.
6. Judge the rise by feel: the dough should be domed, airy and about 50 percent larger.
7. Turn the dough onto an unfloured counter and fold it into a loose round.
8. Rest the round uncovered for 20 minutes.
9. Shape the dough tightly by pulling the edges into the center and rolling it seam side down, dragging it across the counter to build tension.
10. Set the loaf seam side up in the dusted basket, cover it, and refrigerate for 16 hours.
11. Put the Dutch oven with its lid in the oven and heat to 500 degrees F for 45 minutes.
12. Turn the cold loaf out onto a sheet of parchment and slash the top once, half an inch deep, with a razor.
13. Lower the loaf on its parchment into the hot pot and cover it.
14. Bake covered for 20 minutes.
15. Take off the lid, drop the heat to 450 degrees F, and bake 25 minutes more until the crust is deep mahogany.
16. Cool the loaf on a rack for at least 2 hours before cutting, so the crumb sets.