Ciabatta

Ciabatta is the first loaf here built on a preferment. Flour, water and a little yeast are stirred together and left for 12 to 16 hours as a biga, a starter that builds flavor before the main dough is mixed. Making a preferment and judging when it is bubbly and ready is the nearest yeasted rehearsal for keeping a sourdough starter. The dough itself is sticky and soft, and good recipes warn against adding flour unless it is truly soupy, so you practice wet-handed bowl folds and gentle shaping that keeps the big holes intact. It is messy at first, but nothing else on this list gives quite such an open, airy crumb.