Autolyze

1. In a large mixing bowl, combine 350g of unbleached bread flour, with 90g of whole wheat flour. Add 350g of filtered water and mix with your hands, until the flour is well combined, with no dry bits in the bowl. Cover with plastic wrap and let the dough rest for an hour or 2. This will help hydrate the different flours and build the dough structure.
2. Add 90g of ripe sourdough starter and spread this over the autolyzed mixture. Use the tips of your fingers to spread the starter all over the dough. Fold the edges of the dough into the center, ensuring that the starter is fully incorporated. Use your thumb and forefinger to pinch the dough until the starter is well incorporated. Cover and rest for 30 minutes.
3. Sprinkle 9g of salt over the surface of the dough. Then use your fingers to pinch the tiny salt granules into the dough. You shouldn’t feel any salt granules in your dough, so this may take a few minutes depending on the coarseness of your salt. Cover and rest for 15 minutes.

Bulk fermentation

1. Perform 6 sets of stretch and folds in the first two hours of bulk fermentation. The first three sets will take place in 15-minute intervals. Cover and rest the dough at 80F between each set. The dough won’t rise much during this process, though it will become stronger. Dip your hands in water to prevent the dough from sticking to your fingers.
2. Grab the top part of the dough with both hands, and gently pull the dough, stretching it upwards, then fold over the opposite edge. Rotate the bowl 180 degrees and repeat from the other side. Rotate the bowl 90 degrees and repeat again on both sides. This entire process equals a single stretch and fold set. After the stretch and fold, gently lift the dough and round it nicely in the bowl. If you notice your dough developing quickly, simply reduce the number of stretches and folds to 3 or 4 sets, 30 minutes apart.
3. Allow the dough to rest – bulk ferment – covered at 80F for another 1.5 to 2 hours after the final stretch and fold. Keep an eye on the dough. Generally, you should aim to end bulk fermenting once the dough is almost double in size. The total bulk fermentation time will vary depending on the temperature of your kitchen, the dough temperature, and the flour type. Once bulk fermentation is complete, the dough should have expanded, with gas bubbles on the surface and edges of the bowl. The dough should also be rounder. A flat dough will indicate insufficient dough strength.

Pre-shape

1. Transfer the dough onto a clean countertop.
2. Use a bench knife to gently shape the dough into a round, pulling it towards you on the countertop in a circle to create some tension on the dough’s skin. You’ll notice the dough becoming bouncier as you do this.
3. Work quickly and gently, then rest the dough for 15 to 20 minutes or until it has relaxed in time for the final shaping. Pre-shaping gives the dough some extra tension while resting the dough allows the gluten to relax slightly before the final shape.

Final shape

1. Dust a 9-inch round or 10-inch oval banneton basket with rice flour.
2. Add a light sprinkling of bread flour over the surface of the dough. Use a bench knife to lift and flip the dough onto the countertop. Shape the dough into a round or batard depending on the baking vessel.
3. After shaping, gently pick up the shaped dough, and transfer it into a floured banneton, seam side up. Drape a kitchen towel over the banneton and place it into a plastic bag.
4. Seal the bag with a clip, and allow the dough to rest at room temperature for 10 minutes.

Final proofing

1. Place the covered banneton in the refrigerator and cold retard the dough for 15-16 hours at 38 degrees F. This type of cold fermentation will help develop a prominent flavor and improve the final crust texture.

Preheat the oven

1. Preheat your Dutch oven, or combo cooker with the lid on at 500F for at least 1 hour.
2. Once the oven and baking instrument have preheated for an hour, remove the banneton from the fridge and uncover the dough.
3. Test the dough proofing by flouring a small section of the dough. Gently press your finger into the dough, if the dough springs back slowly with a slight indentation, then the dough is ready to bake. If the dough springs back quickly, it is under-proofed and must be returned to the fridge, covered for another hour. If the dough doesn’t spring back at all, then it is over-proofed, and unfortunately, nothing can be done at that stage.

Transfer and bake

1. Place a large piece of parchment paper over the banneton, then flip carefully so that the banneton is upside down. Set it down on your countertop.
2. Trim any extra bits of parchment paper, leaving enough to create two handles, so that you can lift and lower the dough into the preheated Dutch oven. Use a bread lame to score the dough, then carefully transfer the bread dough into the oven.
3. Bake bread at 500 degrees F for 25 minutes.
4. Remove the lid. The sourdough baking process should have enabled the dough to rise and expand, setting the crust beautifully. Reduce the oven temperature to 475 degrees F and continue to bake uncovered for an additional 15-25 minutes until the crust is a wonderful deep golden brown. You might want to rotate the Dutch oven a couple of times during this stage.
5. Carefully remove the bread from the oven and transfer it to a cooling rack. Ensure the sourdough bread has cooled completely before slicing. This can take several hours. If you rushed to slice the sourdough bread you’ll end up with a gummier texture.