Rustic Apple-Rye Bread

Stir together cracked rye berries and 1/2 cup boiling water in a small heatproof bowl. Let stand 1 hour. Stir in buttermilk. Cover and let stand at room temperature overnight (12 to 16 hours).

Stir together 1/4 cup cold water and sourdough starter in a 2-cup liquid measuring cup until starter is mostly dissolved. Stir in flour until smooth. Cover tightly with plastic wrap, and let stand at room temperature until mixture is bubbly, at least doubled in volume, and smells sour like yogurt, 12 to 16 hours.

Combine rye levain and 2 1/4 cups warm water in a large bowl. Stir well until levain is mostly dissolved. Add bread flour and rye flour; mix with hands until all ingredients are well combined with no dry spots. Cover with a clean towel, and let stand at room temperature until dough stiffens slightly, about 30 minutes.

Add salt and remaining 1/4 cup warm water to dough in bowl. Using a squeezing motion, incorporate salt and water into dough. Stretch and fold dough onto itself in bowl until it forms a tight and mostly smooth ball, 3 to 4 minutes. Cover bowl with a clean towel, and let stand at warm room temperature (about 80°F) until airy and slightly risen, about 2 hours, performing a set of stretch and folds (4 folds in every set and rotating bowl 90 degrees after each) every 30 minutes.

Add cracked rye soaker to dough. Stretch and fold dough back onto itself in bowl until cracked rye mixture is mostly combined, about 1 minute. Cover bowl with a clean towel, and let stand until slightly risen, about 1 hour, performing 1 set of stretch and folds after 30 minutes.

Turn dough out onto a lightly greased (with cooking spray) work surface. Using hands, gently stretch dough into a 16- x 12-inch rectangle. Sprinkle evenly with apples, raisins, and cinnamon. Starting from a short end, roll dough up jelly roll–style. Fold one-third of roll in toward center and other third on top, like a letter, and return to large bowl. Cover with a clean towel, and let stand at room temperature 1 hour and 30 minutes, performing 1 set of stretch and folds after 45 minutes.

Turn dough out onto a lightly floured (with rye flour) work surface, and divide in half (about 2 1/2 pounds each). Shape each half into a ball. Cover with a clean towel, and let stand 20 minutes.

Invert a 4-inch bowl, and place it inside of a 9-inch bowl. Line larger bowl with a linen kitchen towel, draping it over inverted bowl to form a ring-shaped moat. Dust towel generously with rye flour. Repeat with a second set of bowls, a towel, and rye flour. Set aside.

Working with 1 dough ball at a time and keeping remaining dough covered, uncover and dust lightly with rye flour. Press bottom of a pint glass (about 21/4 inches wide) firmly into center of dough ball to form an indentation. Keeping dough ball on work surface, poke through center of indention using fingers to form a hole, stretching hole to about 4 inches in diameter, dusting generously with flour as needed to prevent sticking. Invert dough ring onto 1 prepared proofing bowl so that hole in center fits around inverted 4-inch bowl. Repeat process with second dough ball. Cover each bowl with a clean towel, and let stand at room temperature until slightly risen, about 1 hour. Transfer covered bowls to refrigerator, and chill overnight (12 to 16 hours).

Preheat oven to 500°F with a pizza stone on center rack. Place a baking pan (such as a 9-inch round cake pan) on lowest oven rack under pizza stone during final 5 minutes of preheating. Working with 1 loaf at a time and keeping remaining loaf in refrigerator, invert loaf onto a parchment paper–lined baking sheet or a parchment paper–lined pizza peel. Using a small, sharp knife or a lame, cut about 6 (3- to 4-inch-long) slashes (about 1/4 inch deep) into top of loaf.

Slide loaf from parchment-lined baking sheet onto preheated pizza stone. Using a kettle or a measuring cup with a long spout, carefully and quickly pour hot water into cake pan to a depth of about 1/2 inch. Immediately close oven door to trap steam. Reduce oven temperature to 475°F, and bake until loaf is dark golden and internal temperature registers 205°F, 30 to 35 minutes. (Remove cake pan from oven if all water evaporates before loaf is finished baking.) Transfer loaf to a wire rack, and let cool completely, about 2 hours. Meanwhile, repeat process with second loaf, letting oven preheat to 500°F and refilling cake pan with hot water in between loaves.