Preparation

• Day 1: Make the biga/preferment by whisking together the bread flour and yeast. Add water, mix, cover, and let rest at room temperature for 8–24 hours.
• Day 2: Uncover the biga. In a separate bowl, whisk together the yeast and warm water. Let sit for 5-10 minutes, then add biga, flour, and salt, mixing until uniform.
• Cover the bowl and let the dough rest for 30 minutes at room temperature.
• Perform the 1st stretch-and-fold by folding the dough at the 12 o'clock mark and turning the bowl for a total of 8 folds. Rest 30 minutes.
• Repeat the stretch-and-fold process three more times with 30-minute rests in between. After the last stretch-and-fold, refrigerate the dough for at least 1 hour.
• Lightly flour your work surface, scrape the dough onto it, and shape into a rough rectangle. Cut into 8 rolls or 2 loaves.
• Transfer the rolls to floured parchment paper, ensuring they are at least 2 inches apart. Cover and let rest for 1 hour.
• Preheat the oven to 450°F (232°C), positioning racks and heating a baking sheet.
• Scatter ice cubes in a metal roasting pan and uncover the rolls. Optionally spray with water. Transfer the proofed dough to the preheated baking sheet and bake.
• Bake for 20–25 minutes until golden brown and hollow-sounding when tapped. Let cool for at least 45 minutes before slicing.