Mix the water and starter

• Add 350 g of warm or room temperature filtered water to a bowl.
• Add 100 g of active sourdough starter.
• Take the bowl off the scale and mix well until the water is nice and milky.

Add flour and salt

• Put the bowl back on the scale and add 500 g of flour.
• Add 10 g of fine sea salt.
• Take it off the scale and mix well, starting with a bread whisk and then finishing with your hands.

First rest

• Cover the bowl with Saran wrap.
• Let the dough rest for about 20 to 30 minutes.

Stretch and fold (set 1)

• Wet your hands a little bit.
• Do your first stretch and fold: pull, fold, twist, and repeat until the dough is worked.
• Cover it and rest for another 20 to 30 minutes.

Stretch and fold (set 2)

• Wet your hands again.
• Do the same stretch and fold.
• Cover it and let it rest for another 20 to 30 minutes.

Stretch and fold (set 3)

• Wet your hands again.
• Do your final stretch and fold. The dough should feel soft but be harder to stretch at this point.
• Do a few coil folds to get the dough nice and round.

Bulk ferment

• Let the dough bulk ferment for about a couple of hours.
• Wait until it doubles in size and isn't sticky to the touch.

Shape the dough

• Turn the dough out and shape it into a little rectangle.
• Do an envelope fold and then roll it up.

Banneton and cold proof

• Flour your banneton basket really nicely.
• Plop the dough in there and do some stitching.
• Cover it with Saran wrap and put it in the fridge to bake tomorrow.