Remove 3-4 tablespoons from the water and dissolve the yeast in it. Mix the remaining water with salt, add the flour and finally the yeast water and knead for at least 10 minutes to form a smooth dough. Put the lid on the bowl and let it ferment for 24 hours. Every 4-6 hours, stretch and fold the dough.
Then place the dough on a floured work surface and shape it tightly (round or long). Put the formed dough on a floured linen cloth in a bowl and let it ripen for another hour.
Place a cast iron saucepan with a lid in the oven and preheat to 250 ° C O / U. When the oven has reached heat, remove the pan. Meanwhile, cover a large wooden board with baking paper and place on the dough bowl. Turn the bowl with the board once so that the dough lies on the baking paper. Remove the bowl and cloth and lift into the hot saucepan with the baking paper. Close the lid and place in the oven.
Set the temperature back to 230 ° C and bake for 45 minutes. If you want a nice dark crust, take the lid off after 15 minutes.