Step-by-Step Instructions

1. 1.Combine Starter and Water

   Add 120g (1/2 cup) of active sourdough starter to a large bowl. Pour in 310g (1 1/3 cups) of warm filtered water (around 90°F or 32°C). Stir until the starter is mostly combined with the water.

2. 2.Add Flour and Salt for Autolyse

   Add 500g (4 cups plus 2 tbsp) of bread flour and 16g (2 tsp) of fine sea salt to the bowl. Mix with a spatula or clean hands until the ingredients are just combined into a shaggy mixture, ensuring there are no dry pockets of flour remaining. Do not overmix.

3. 3.Autolyse

   Cover the bowl with a damp kitchen towel. Let the dough rest at room temperature for 1 hour. This step allows the flour to fully hydrate and gluten to begin developing.

4. 4.First Set of Stretch and Folds

   After 1 hour, wet your hands in clean water. Reach into the bowl, lift a portion of the dough from one side, and gently stretch it upwards before folding it over itself. Rotate the bowl 90 degrees and repeat this process 3 more times, completing a total of 4 folds. Cover the bowl again with the damp towel and let it rest for 20 minutes.

5. 5.Repeat Stretch and Folds

   Repeat the stretch and fold process (4 folds) three more times, ensuring a 20-minute rest period between each set of folds. This helps to further develop the gluten structure of the dough.

6. 6.Shape the Dough

   After the final set of folds and rest, gently release the dough from the bowl using a wet spatula if needed. Lightly flour your work surface. Gently transfer the dough onto the floured surface. Gather the corners of the dough to form a rough ball, pinching the seams together at the bottom.

7. 7.Tighten the Dough Ball

   Using your hands, gently cup the dough ball and scoot it towards you on the floured surface. Rotate the ball slightly with each scoot to create tension on the surface, forming a tight, smooth ball. Repeat this motion until the ball is firm and holds its shape.

8. 8.Prepare for Final Proof

   Line a smaller bowl or colander with a clean, smooth kitchen towel (not terry cloth). Liberally sprinkle the towel with flour, ensuring all surfaces that will touch the dough are well-dusted.

9. 9.Final Proof (Cold Fermentation)

   Gently scoop the shaped dough ball into the floured towel-lined bowl, placing it smooth side down. Cover the bowl with the towel and then seal it tightly with plastic wrap to prevent drying. Refrigerate for 12 hours (or up to 36 hours) for a slow, cold fermentation, which develops a deeper, more complex sourdough flavor. Alternatively, you can let it rise at room temperature for 6-12 hours.

10. 10.Preheat Oven and Cast Iron Pot

    Approximately 1 hour before baking, place a cast iron pot with its lid into the oven. Preheat the oven to 500°F (260°C). If your dough was refrigerated, take it out to warm up on the counter while the oven preheats.

11. 11.Score the Dough

    Once the oven is preheated and the dough has proofed, place a piece of parchment paper over the dough in the proofing bowl. Carefully flip the dough onto the parchment paper. Gently remove the towel. Using a sharp blade (like a lame or razor), make a light score across the top of the dough, just piercing the skin, to allow for expansion during baking. You can create a simple cross or a decorative design.

12. 12.Bake Covered

    Carefully remove the screaming hot cast iron pot from the oven using oven mitts. Carefully lift the dough by the parchment paper and transfer it into the hot pot. Carefully place the lid back on the pot. Return the pot to the oven and bake for 20 minutes at 500°F (260°C).

13. 13.Bake Uncovered

    After 20 minutes, reduce the oven temperature to 450°F (230°C). Carefully remove the lid from the pot. Continue baking for another 20 minutes, or until the crust is a deep golden brown and sounds hollow when tapped.

14. 14.Cool and Serve

    Carefully remove the bread from the pot using the parchment paper and transfer it to a wire rack. Allow the bread to cool completely on the wire rack before slicing. This is crucial for the internal structure to set. Once cooled, slice and serve with butter and a sprinkle of salt.