This is a super-hydrated dough, almost bordering on a liquid state, and it takes gentle handling to keep in the large air bubbles characteristic of a classic Ciabatta. Follow the steps carefully and you’ll have cracking Ciabatta loaves.
Mix together the ingredients for the pre-ferment in a bowl. Cover it with cling film (plastic wrap) and allow to develop either in a cool kitchen or in the fridge for at least 4 hours; preferably overnight. Once developed the pre-ferment should be bubbly and will have increased in volume.
Combine the pre-ferment with the additional flour, water, salt