Sourdough Boule

Feed your starter 4-8 hours before you mix, so it is at its peak when it goes in.

Test it by dropping a teaspoonful into a glass of water: a starter at its peak floats, and one that sinks wants feeding again before you start.

Mix the white and wholemeal flours with the 340ml of water until no dry flour is left.

Cover and rest for 60 minutes.

Give it the full hour. This is the autolyse, and the flour hydrates and begins forming gluten on its own — an hour of kneading you do not have to do.

Add the starter and pinch it through the dough for 2 minutes, until no streaks are left.

Add the fine salt and the 25ml of water and squeeze the dough through your fingers until it feels smooth again.

Cover and ferment at 22-24C/72-75F for 4-5 hours.

Perform four sets of stretch-and-folds in the first two hours, 30 minutes apart, lifting one side of the dough, stretching it up and folding it over the middle, then turning the bowl a quarter turn and repeating four times.

Leave it undisturbed after the last fold.

Stop the bulk when the dough has risen by half to two-thirds, domed at the surface and wobbles as one mass when you shake the bowl.

Do not wait for it to double. Sourdough taken too far in bulk goes slack and soupy, spreads flat the moment it is turned out and bakes into a dense gummy crumb, and nothing later in the process recovers it.

Scrape the dough onto an unfloured worktop.

Pre-shape it into a loose round by dragging it towards you in quarter turns with a scraper.

Rest it uncovered for 30 minutes, until it has relaxed and spread slightly.

Shape it again more tightly: fold the edges into the middle, turn it seam-side down and drag it across the bare worktop in short pulls until the surface pulls tight and smooth.

Keep the worktop free of flour underneath it. Flour is precisely what stops the skin gripping the surface, and without that grip there is no tension to build.

Dust a banneton or a cloth-lined bowl heavily with rice flour.

Lift the loaf in seam-side up.

Cover and refrigerate for 12-16 hours.

Heat the oven to 240C/475F with a lidded cast-iron pot inside it, and give it a full 45 minutes at temperature, since the pot comes up to heat far more slowly than the air around it.

Turn the cold loaf out onto a square of baking paper.

Score it once, a single slash about 1cm deep held at a shallow angle to the surface.

Make that one decisive cut through the skin. A timid, shallow score seals over in the first few minutes and the loaf tears itself open at the side instead.

Lower the loaf on its paper into the hot pot and put the lid on.

Bake covered for 20 minutes at 240C/475F.

Take the lid off and turn the oven down to 220C/425F.

Bake for a further 20-25 minutes, until the crust is dark brown all over.

Take it darker than feels comfortable. Most of what a sourdough crust tastes of is made in the last five minutes, and a pale loaf tastes of paste.

Check the centre with a thermometer if you have one: 96C/205F.

Cool on a rack for at least 2 hours, and listen for the crust crackling as it contracts.

Do not cut it warm. The crumb is still setting, and a knife through a hot loaf drags it into a gummy paste that never recovers.

The no-knead sourdough focaccia in this collection uses the same starter with none of the shaping, and is the easier place to start if this is a first loaf.