Sourdough starter + flour + water (350 g)
Autolyse 30 minutes.
Add salt and gradually incorporate water in 10 g portions until the desired consistency is reached. The dough shouldn't be runny but smooth.
Keep the temperature no higher than 25 °C — this is very important! The warmer your environment, the colder the water should be.
Ferment in an oiled container at a dough temperature of 23-25 °C for 4-6 hours until it increases 4 times. Don't be afraid of over-fermenting.
Fold the dough every 15 minutes while incorporating the oil, then fold every 30 minutes.
For the last 2-3 hours, do not fold. You can finish fermentation in the cold (from 1 to 12 hours or more, depending on the degree of fermentation of the dough). In any case, it's better to let it rest in the cold before shaping.
Shape into 4 ciabattas and preheat the oven with or without a baking stone.
Proofing on cloth during the time the oven is heating up.
With a gentle motion, turn the ciabatta onto a board and drop it onto the stone or baking tray. Bake with steam at 240 °C for 20 minutes. If necessary, reduce the temperature to 230 °C.