First stage- chef
¼ cup sourdough starter
¼ cup warm water
¾ cup bread flour, plus about another ¼ cup for kneading
Mix dough together, then knead about 5 minutes using bench scraper and adding flour as needed. Put in oiled bowl, cover with plastic, let rise until doubled, 5-6 hrs.
All of the levain (from above)
1/2 cup warm, chlorine-free water
1 1/2 cups King Arthur Unbleached Special Bread Flour
"Refresh" the levain by placing it in a medium-sized bowl, chopping it into small pieces, and adding the water and 1/2 cup of the flour, stirring till smooth. Add the remaining flour gradually to create a stiff dough. Knead the dough for several minutes, then return it to the bowl, cover it with a damp cloth, and let it rise for 3 to 5 hours, till it doubles in size. Punch down the risen levain, and reserve 1/4 cup as your next chef. (Let the piece ferment at room temperature for 3 hours, then wrap it in plastic and store it in the fridge. It'll develop a hard crust; that's OK.)
all of the second-stage levain (from above)
3/4 cup warm, chlorine-free water
2 teaspoons salt
2 cups King Arthur Unbleached Special Bread Flour
Chop the levain into small pieces, and mix them with the water, stirring till they begin to dissolve. Add the salt, then 1 1/2 cups of the flour. Turn the dough onto a lightly floured or lightly greased work surface, and knead until the dough is smooth and satiny, adding only enough additional flour to keep the dough from sticking unbearably. Return the dough to the bowl, cover it with a damp cloth, and let it rise in a warm place for 8 to 10 hours.
Shaping: Cut the dough into 2 pieces, and shape each piece into a round or oval. Transfer the loaves to a lightly greased or parchment-lined baking sheet, or to a floured banneton; cover with a heavily floured cloth, and allow them to rise for 2 to 3 hours, or until they're almost doubled in bulk.
Don't slash or glaze the loaves. Bake the bread in a preheated 450°F oven for 35 to 40 minutes, or until they're a deep, golden brown. Yield: 2 loaves.