A classic country loaf made with discard sourdough starter. Adapted from Tartine Bread.
Pour 350 g cold spring water into a large wide mixing bowl, and add the discard starter, mixing to disperse the starter a bit.
Use your hands and/or a bowl scraper to mix in the all-purpose flour (or bread flour) and whole wheat flour until no dry bits of flour remain.
Allow the flour/water/starter mixture to rest for 25-30 minutes.
Add the salt and the remaining 25 g cold spring water to the bowl, working it in with your hands.
Transfer the dough to a large, clear, well-insulated container and cover the container with plastic wrap. Allow the dough to rest for 30 minutes.
After the 30-minute rest, complete three sets of stretch-and-folds, separated by 30 minutes. (In other words: if you do the first stretch-and-fold at minute zero, you'll do the second at thirty minutes, and the third at the end of the hour.)
Leave the dough in the covered container at warm room temperature (approx. 75 F) for 10-12 hours. You're looking for a 60% to 90% increase in volume. If you get home from work and the dough has not increased in volume, place the container in a turned-off oven with the pilot light on to speed the end of the bulk rise. For those who need a visual, here is my dough right after I transferred it to the bulk rise container--you'll see that it doesn't quite reach the 1 L mark; I generally wait until the dough has risen to about halfway between 1 L and 2 L before shaping.
Turn the dough out, pre-shape it, and allow it to rest for 15-30 minutes.
Shape the loaf as desired, and transfer it to a cloth-lined banneton that has been dusted with a mixture of white rice flour and all-purpose or bread flour.
Cover the banneton (I use a plastic shower cap), and leave it in the refrigerator overnight.
To bake the bread in a pre-heated dutch oven: In the morning, place your cast iron dutch oven (with lid) in the oven, and pre-heat the oven to 500 F.
When the oven has reached temperature, remove the banneton from the refrigerator, dust the top of the dough with white rice flour, and turn the loaf out onto a piece of baking parchment. Dust the loaf with flour (or not), and score as desired.
Using the parchment, carefully transfer the loaf to the pre-heated pot Replace the lid, and immediately place the pot in the oven.
Bake the loaf covered at 500 F for 20 minutes, then remove the lid, reduce the oven temperature to 450 F, and continue baking for another 25-35 minutes--until the crust is sufficiently dark for your taste.
To bake the bread with a cold start: In the morning, remove the banneton from the fridge, turn out the loaf onto a piece of parchment and score it as above. Place the scored loaf with parchment in an unheated dutch oven. Replace the lid, and transfer the pot to a cold oven.
Heat the oven to 500 F. Once the oven temperature has reached 500 F, bake the loaf in the covered pot for 20 minutes more. After the loaf has baked in the covered vessel for 20 minutes at 500 F, remove the lid, reduce the oven temperature to 450 F, and bake for 25-35 minutes uncovered.
Allow the loaf to fully cool on a wire rack before slicing.