Mix sourdough starter, flour, and salt together. Add 1 cup water, then more as needed to make a moist bread dough.
Knead dough until it passes the “window pane test.” That is, a small piece of dough will stretch between four fingers thin enough to allow light to pass through without breaking.
Split the dough in half. Shape each half into a loaf.
Place in a loaf pan (9 x 5 x 3 inches), proofing basket, or on a board. Cover lightly with a towel and proof 4-24 hours. While a second proofing period is not required, if desired, punch dough down after 4-12 hours, reshape, and proof again.
Slice an X shape in the top of the loaf with a very sharp knife or razor blade to allow the loaf to expand during baking without splitting in unexpected places.
Bake at 400°F for 30-60 minutes, depending on loaf size, or until the internal temperature reaches 190° to 210°F. Use an instant-read thermometer inserted into the bottom or side of the loaf.
Cool before slicing. Makes two standard loaves.
Three Critical Steps for a Light and Fluffy Loaf
#1: Very Active Fresh Sourdough Starter
Very active yeast and bacteria are critical for proper leavening of bread dough. If your sourdough starter has been stored in the refrigerator, it has been living in a dormant state. Plan to remove the starter from the refrigerator 1 to 2 days in advance and feed it at least three times prior to baking. Follow the instructions for Making Fresh Sourdough Starter to ensure that your starter is active and ready to use for baking.
#2: Adequate Kneading to Activate the Gluten
Thoroughly kneading the dough is a critical step to allow the gluten to fully develop.
If kneading by hand, plan for at least 20 minutes of kneading, taking breaks if needed. For example, knead for 5-10 minutes, take a break, then knead 10-15 minutes more.
If using a mixer, take care that the dough does not overheat, which can damage the yeast. Always knead the last 5 minutes by hand. When the dough passes the window pane test, it has been kneaded sufficiently. If it breaks before being stretched thin, continue kneading.
#3: Plan for a Long Proofing (rise) Period
As a natural yeast, sourdough tends to take significantly longer to rise than dough made with commercial yeast. Timing is dependent on the specific starter and conditions in your home, and may vary widely. Plan for a 4- to 12-hour rise period. If you desire more sour bread, plan for 12-24 hours. Learn more about adjusting the sourness of your sourdough bread.