Mix water with flour and starter. Be sure that all flour is hydrated. Cover it with cling film and let it ferment for 12 hours at room temperature.

Mix all ingredients except salt. Be sure that all flour is hydrated. Let it rest for an hour.

Add the salt and stretch and fold if you don't have a dough mixer. I repeated every 30 minutes, 4 times in total. I normally stretch 4 times each set. Total time for bulk fermentation was 3 hours. If you have a mixer you just run it on a medium speed until the dough is smooth and stretchy.

Scrape out the dough onto a floured working surface. Stretch out the dough carefully to a rectangular shape. Try to degass the dough as little as possible. Let it rise for 1 hour. Pre heat the oven to 480ºF / 250ºC with two oven plates. If you have a baking stone you should place it on the upper plate.

Cut the dough in half lengthways and divide each half into strips. Transfer the dough stripes to a parchment paper. Slide the dough stripes and parchment paper into the oven and bake for approx. 20 minutes. Pour water on the bottom plate to get some steam.

Let the ciabattas cool on a wire rack.