Steps

1. At least 2 hours before beginning (you can do this the night before), feed the levain as follows: Remove from the refrigerator and add equal parts flour and room-temperature water (I use about 130 grams each, which replenishes what I’ll be using in the bread). Stir well, incorporating oxygen, and leave on the countertop with the cover slightly ajar. The starter should be bubbling and lively when you begin your bread.
2. Place a large mixing bowl on a kitchen scale and add each ingredient in turn, using the tare button to zero out the scale between additions. Mix thoroughly with a wet hand until the dough is homogeneous. Cover and leave the dough to autolyse for about 25 minutes.
3. Remove the dough to an unfloured countertop and knead by hand for 7 to 9 minutes (or if you insist, you can use a stand mixer with a dough hook for 2 to 3 minutes) until the dough is elastic and smooth. During the first minutes of kneading, a metal bench scraper is useful for scooping up the wet dough that clings to the countertop.
4. Clean out the bowl (no soap, please), mist with oil spray, and replace the dough, topping with a piece of oiled plastic wrap. Ferment at room temperature (68 to 72 degrees is ideal) for 4 to 5 hours.
5. Remove the dough, which should have risen by about half, to a lightly floured countertop and gently press into a disk about 1 inch high. Form a boule by gathering the sides into the center, creating surface tension, then place seam side up in a colander covered with a well-floured linen napkin. Return the plastic wrap atop the dough and set aside to proof.
6. Meanwhile, place a pizza stone in the lower third of the oven and an old cast-iron skillet or pan on the bottom shelf. Preheat the oven to at least 500 degrees.
7. After 1½ to 2 hours, carefully turn the loaf onto a baker’s peel that has been liberally sprinkled with rice flour or cornmeal. Sprinkle the top of the loaf with rye or rice flour (not white flour, which turns brown) to get that country “dusted” look.
8. Make several symmetrical slashes (grignes) with your lame or a single-edged razor.
9. Immediately slide the loaf onto the stone and add 1 cup water to the skillet (wear an oven mitt), minimizing the time the oven door is open. Reduce the oven temperature to 480 degrees.
10. After 20 to 25 minutes, or when the loaf has turned dark brown, reduce the oven temperature to 425 degrees.
11. Continue baking until the loaf registers 210 degrees in the center (about 50 to 60 minutes total) with an instant-read thermometer, or until a rap on the bottom of the loaf produces a hollow, drumlike sound. Return the bread to the oven, with the oven off, for about 15 minutes.
12. Allow the bread to cool on a rack at least 2 hours before serving.