Make a Mature Starter:

1. In a clear glass container, mix together the starter, flour, and water. Mix well and place a rubber band around the glass where the top of the mixture is. Wait 4 or so hours until the mixture doubles. This will vary based on how active the starter is and how warm your kitchen is.

Make the Dough:

1. Mix the first three flours for the bread with the water with your hands. Let this sit for 30 minutes. This will hydrate the flour.
2. Add 200 grams of the mature sourdough starter and the salt to the hydrated dough. Mix this well with your hands, cover with a damp towel for 30 minutes.

Stretch and Fold:

1. Stretch the dough really high and fold it underneath the other side of the dough, do this 3x around. Do this process 3x over every 15 minutes.
2. Preform the same process, every 30 minutes 3 more times.
3. Cover the dough with a wet towel or plastic wrap and wait for it to double (usually 12 hours or overnight for me).
4. Place flour or rice flour (I love to use rice flour because it helps the bread look beautiful after it's baked) on a flat surface, I like to use a pastry mat. Place the risen dough on the mat and cut it in half with a dough scraper. Try your best to keep all air bubbles in tact.
5. Shape each piece into a bowl, fold the dough on top of itself, flip it over and spin the dough towards you. You can watch me do this in my youtube video here: https://youtu.be/FsBNxXif_yA .
6. Set the dough out for 15 -20 minutes. Shape again and add it to a flour benneton or a glass bowl. Cover and refrigerate for 12-15 hours.

Bake the Bread:

1. Add an empty dutch oven to your oven at 500 degrees for 1 hour.
2. 5 or 10 minutes before the hour is up score your bread on a piece of parchment paper. You can watch me score the bread here https://youtu.be/FsBNxXif_yA (basically you're putting a big gash in the bread so the steam can escape).
3. Pick the bread up on the parchment paper and place it in the bottom of the dutch oven. Cover and bake at 500 for 20 minutes.
4. After 20 minutes, remove the cover and decrease the temperature to 475 degrees for another 25 minutes.
5. Remove from the dutch oven and place on a cooling rack. Let the bread cool for another 20 minutes at least before cutting it.