Mix the dough

• Stir together the water, sourdough starter and salt in a bowl.
• Add the bread flour and stir until you have a sticky dough ball.
• Cover the bowl and let rest.

Stretch and fold

• With wet hands, perform a series of stretches and folds.
• If time permits, repeat the stretches and folds at 30-minute intervals three more times.
• By the fourth set the dough should be smooth, strong and elastic.

Bulk rise

• Transfer the dough to a straight-sided vessel to gauge the rise.
• Let it rise until it increases in volume by about 75%.

Shape the dough

• Turn the dough out onto a lightly floured work surface and let it rest.
• Stretch it out, fold it envelope style, then turn and roll it into a tight coil.
• Use flour very sparingly to build tension in the dough.

Cold proof

• Line a proofing basket with a flour sack towel and place the dough in it seam side up.
• Pinch the seam closed, fold up the towel and tuck the whole basket into a bag.
• Transfer to the fridge.

Score and bake

• Turn the dough out onto a piece of parchment paper and score it with a simple slash.
• Transfer the dough to a preheated dutch oven, cover and bake at 450 °C.
• Remove the lid and return to the oven at 400 °C.

Finish baking

• Bake uncovered until deeply browned and crusty.

Cool before cutting

• Transfer the baked loaf to a cooling rack.
• Let it cool completely before cutting so the crumb isn't gummy.