Sourdough bread

Mix the starter with the bread, whole wheat and rye flours and the water to make a levain.

Cover loosely and leave at room temperature about five hours, until roughly doubled, bubbly and very active.

About three hours into the levain, mix the wheat flour and bread flour, make a well, and add the water; mix until combined. This is the autolyse.

Scrape down and cover; let it sit two hours so the flour hydrates, the wheat flour especially, which makes the dough easier to work with.

If the levain is ready before the autolyse has had two hours, start anyway; even an hour is fine.

Add 70 grams of the levain to the dough and the salt around the outside of the bowl, then fold with wet fingers to mix both in evenly.

Work it a couple of minutes into a relatively uniform ball, cover, and set a timer for 15 minutes.

Flop and turn: with wet fingers grab the dough at the edge of the bowl, flop it over the top, turn the bowl a couple of inches and grab where the crease formed; keep going until the dough springs back and resists.

Turn the dough over and slide damp hands underneath to draw a smooth skin over the top.

Do three sets of the flop and turn, 15 minutes apart, to build gluten structure.

After the last one set the timer for 30 minutes, then move to the counter; rub a few drops of water on the surface first so the dough does not stick.

Stretch and fold: slide fingers under the corners and stretch to a square about 12 inches wide, fold the corners into thirds, fold the top half back, then put thumbs in the centre, fold the dough back and roll it up towards you, stretching as you go.

Turn it back into a ball with damp hands or a flat bench scraper held at an angle, pushing with the side of the scraper at the end so the top stretches taut.

Return it to the bowl and repeat the stretch and fold twice more, 30 minutes apart, for six folds in total.

Bulk ferment on the counter about four hours, until bubbly and about doubled, so the dough jiggles when the bowl is wiggled; the time depends on kitchen temperature.

Scrape onto the counter and pre-shape with the same stretch, fold and ball move, gently, patching anything that tears; dust the top with flour and rest 30 minutes.

Dust the counter, flop the dough over flour side down and do a final trifold, gently, then shape it into a high, tight round with a smooth taut skin.

Dust the top with flour, slide the bench scraper under, flip onto your hand and lower it gently into the rice-floured banneton.

Stitch the dough: pull some dough up over the top from one side and then the opposite side, three or four times, to tighten the skin, then sprinkle a little flour around the edge.

Cover and proof in the fridge overnight; bake exactly 14 hours after it goes in.

An hour before baking, put the pan in the oven and preheat to 500F.

Turn the dough out onto the parchment and score at a 45 degree angle about a quarter inch deep, right across the loaf about one third in.

Transfer the loaf on its parchment into the hot pan, add the two ice cubes one at each end, and put the lid on.

Bake covered at 500F for exactly 20 minutes.

Take the lid off, lower the heat to 450F and bake another 35 minutes.

Cool one hour before slicing, or the loaf loses steam and comes out drier.