Rustic Italian Bread

FOR THE BIGA: Combine flour, yeast, and water in bowl of standing mixer fitted with dough hook. Knead on lowest speed (stir on KitchenAid) until it forms a shaggy dough, 2 to 3 minutes. Transfer biga to medium bowl, cover tightly with plastic wrap, and let stand at room temperature until beginning to bubble and rise, about 3 hours. Refrigerate biga at least 8 hours or up to 24 hours.

FOR THE DOUGH: Remove biga from refrigerator and let stand at room temperature while making dough. Combine flour, yeast, and water in bowl of standing mixer fitted with dough hook; knead on lowest speed until rough dough is formed, about 3 minutes. Turn mixer off and, without removing dough hook or bowl from mixer, cover bowl loosely with plastic wrap; let dough rest 20 minutes.

Remove plastic wrap, add biga and salt to bowl, and continue to knead on lowest speed until ingredients are incorporated and dough is formed (dough should clear sides of bowl but stick to very bottom), about 4 minutes. Increase mixer speed to low (speed 2 on KitchenAid) and continue to knead until dough forms a more cohesive ball, about 1 minute. Transfer dough to large bowl (at least 3 times dough’s size) and cover tightly with plastic wrap. Let dough rise in cool, draft-free spot away from direct sunlight, until slightly risen and puffy, about 1 hour.

Remove plastic wrap and, following illustrations from "Step by Step: Turning the Dough", turn dough. Replace plastic wrap; let dough rise 1 hour. Turn dough again, replace plastic wrap, and let dough rise 1 hour longer.

TO SHAPE THE DOUGH: Dust work surface liberally with flour. Gently scrape and invert dough out of bowl onto work surface (side of dough that was against bowl should now be facing up). Dust dough and hands liberally with flour and, using minimal pressure, push dough into rough 8- to 10-inch square. Following illustrations from "Step by Step: Shaping the Loaf", shape dough and transfer to large sheet parchment paper. Dust loaf liberally with flour and cover loosely with plastic wrap; let loaf rise until doubled in size, about 1 hour. Meanwhile, adjust oven rack to lower-middle position, place baking stone on rack, and heat oven to 500 degrees.

TO BAKE: Using a lame, single-edged razor blade, or sharp chef’s knife, cut slit 1/2 inch deep lengthwise along top of loaf, starting and stopping about 1 1/2 inches from ends; spray loaf lightly with water. Slide parchment sheet with loaf onto baker’s peel or upside-down baking sheet, then slide parchment with loaf onto hot baking stone in oven. Bake 10 minutes, then reduce oven temperature to 400 degrees and quickly spin loaf around using edges of parchment; continue to bake until deep golden brown and instant-read thermometer inserted into center of loaf registers 210 degrees, about 35 minutes longer. Transfer to wire rack, discard parchment, and cool loaf to room temperature, about 2 hours.