7:00 AM: In a small glass jar, whisk your 5g of starter culture into 35g of water. Add the 30g of bread flour and 5g of rye flour, stirring thoroughly with a small spatula until no dry clumps remain. Cover loosely and let it ferment at a room temperature of 74–78°F (23–26°C) for 8 to 10 hours until it at least triples in volume and peaks.

Toast your 45g of walnuts in a dry pan or oven until fragrant. Place the roasted walnuts into a clean container, cover them completely with the 250g of water, and leave them to soak on your counter until needed.

5:00 PM: Set a fine-mesh strainer over a bowl and drain the purple water completely away from your soaked walnuts. Set the wet nuts aside.

In your stand mixer bowl, combine 207g of that dark walnut water, the 270g of bread flour, and 30g of stone-ground whole wheat flour. Mix cleanly just until the flour is hydrated and forms a shaggy mass. Cover and let it rest undisturbed for 1 hour for the autolyse phase.

6:00 PM: Add 60g of your mature peaked levain starter directly to the autolyzed dough mass. Mix on a low speed for 2 to 3 minutes (or if using a KitchenAid mixer, run it on speed 3 for 3 to 4 minutes) until well incorporated. Cover and let rest for 30 minutes.

6:30 PM: Add the 6g of salt along with the 15g of reserved extra walnut soaker water directly to the bowl. Mix on a low speed for 2 to 3 minutes (or with a KitchenAid on speed 3 for 5 to 6 minutes) until the dough wraps smoothly around the hook but remains sticky at the bottom. Cover and let rest for 30 minutes. Meanwhile, roughly chop your soaked walnuts and weigh out the 45g of dried cranberries.

7:00 PM: Mist your clean work surface generously with water and wet your hands thoroughly. Transfer the sticky dough out onto the damp counter and gently pull it from the edges, stretching it out as thin as possible into a wide sheet without ripping it.

Distribute all of your chopped walnuts and the 45g of dried cranberries evenly across the entire surface of the stretched dough sheet. Fold the dough back over onto itself into a neat envelope packet and return it to a covered container to rest for 45 minutes at 74–78°F (23–26°C).

Build the dough's internal structural integrity systematically by performing three separate rounds of wet-handed stretch-and-folds spaced out over the evening:

* 7:45 PM: 1st Stretch-and-fold.

* 8:30 PM: 2nd Stretch-and-fold.

* 9:15 PM: 3rd Stretch-and-fold.

After your final stretch, let the dough proof undisturbed for 30 minutes at 76–80°F (24–27°C). Monitor the dough mass; look for visible surface bubbles and a clean 40% to 50% increase in volume before moving forward.

9:45 PM: Transfer the dough out onto your work surface and dust its top lightly with flour. Flip the dough over so the floured side faces directly down.

Fold the dough cleanly onto itself so that the dry, floured surface remains entirely on the outside of the loaf (this forms your signature crunchy crust). Shape into a neat round boule and let it rest on your workspace for 30 minutes completely uncovered.

10:15 PM: Dust the top of the relaxed dough with flour. Use your dough scraper to flip it over onto the workspace so the floured side is down again.

Starting at the side closest to you, pull the right two corners of the dough to the left, then fold them up into the upper half of the dough mass. Repeat this folding action cleanly on the left side as well.

Finally, roll the dough smoothly from top to bottom, shaping it into a tight, smooth, and taut roll.

Transfer the shaped roll seam-side up into a prepared proofing basket. Cover it securely with plastic wrap and return the dough to an 80°F (27°C) warm environment for 15 minutes.

Transfer the covered basket into your refrigerator to undergo a slow, cold fermentation for 14 to 24 hours.

Next Morning: Place your cast iron pan with its lid inside the oven and preheat completely to 500°F (260°C) for 45 minutes to a full hour.

Remove the cold dough directly from the refrigerator. Gently invert the basket to flip the dough out onto a sheet of parchment paper. Use a sharp razor or scoring lame to cut a clean, definitive slash across the top.

Use the parchment corners to lift and transfer the loaf directly onto the hot cast iron pan. Secure the lid tightly to capture the expanding steam and bake at 500°F (260°C) for exactly 15 minutes.

Carefully remove the lid, lower the oven temperature down to 450°F (230°C), and continue baking uncovered for an additional 20 minutes until the crust turns an even, deep golden brown. Let the loaf cool completely on a wire rack for 2 hours before slicing.