Ciabatta

In a large bowl, mix the poolish, remaining water, yeast, and olive oil. Add the flour and salt. Mix until a very wet, sticky dough forms.

Leave the dough in the bowl. Over the next 2 hours, perform 4 sets of "stretch and folds" (wet your hands, grab the underside of the dough, stretch it up, and fold it over itself) every 30 minutes. The dough will gain structure.

Let the dough bulk ferment until it is very bubbly and tripled in size (about 1-2 hours).

Generously flour a work surface and turn the wet dough out gently to avoid deflating it. Dust the top with flour and carefully divide the dough in half using a bench scraper. Gently shape each half into a rough rectangular "slipper" shape. Transfer to a well-floured couche or parchment paper. Proof for 45 minutes.

Preheat the oven to 450°F (230°C) with a baking stone and a steam pan. Slide the loaves onto the hot stone, pour water into the steam pan, and bake for 25-30 minutes until the crust is deep brown and feels firm and hollow.