Basic Sourdough Loaf

Directions

1. 1
   Mix together the starter, water, and 3 cups of flour in a bowl until fully incorporated. Loosely cover and let rest in a warm place for 4 hours. Transfer to the fridge and let rest overnight.
2. 2
   Twelve hours later, add the remaining dry ingredients and knead until incorporated. Cover and let rise until light and bubbly, from 3 to 5 hours, folding the dough once an hour by stretching the edges into the center and turning it over.
3. 3
   Divide the dough in half and shape into two loaves on a baking sheet lined with parchment. Cover loosely with lightly oiled plastic wrap and let rise until puffy (2 to 4 hours). Toward the end of proofing, preheat the oven to 425° F with a cast-iron skillet on the bottom rack. Prep a cup of very hot tap water.
4. 4
   Score your loaves and add them to the oven. Quickly (and carefully; steam burns hurt!) pour the hot water into the cast-iron skillet and close the door. Bake for 25 to 35 minutes, until golden brown.