In a large bowl mix together 250 g of strong bread flour, 300 ml warm water and a 100 ml/grams of your sourdough starter, cover with a plastic bag and leave somewhere warm overnight or for at least 8-14 hrs.

The next day add 300 g of strong bread flour and 12g salt and kneed as normal. The dough will be quite sticky. Form tight round and leave to rise in the bowl.

After about 1hr, tip out the dough, lightly stretch the dough and form it back to a tight round. Leave it to rise for another hour.

Repeat the process once or twice, depending on how much time you have and how strong your sourdough bread starter is.

When you are ready for the final shaping of the dough, fully deflate the dough with your hands and shape into one large or two smaller loaves.

Leave the dough to rise until it doubles in size (this time it might take anything from 1 hr to 4 hrs).

Carefully place the dough on a baking tray and slash the top with a knife at this point.

The oven should be as hot as you can make it (250 C) and after 10 mins reduce it to about 200 C. Bake for about 35 mins (in total) and check by tapping on the bottom of the bread, to see when it is ready.

Cool on wire rack.