Gather all ingredients and ensure your sourdough starter has been fed and is active (bubbly and doubling in size within 4-8 hours of feeding). In a large mixing bowl, combine the bread flour, rye flour, and spelt flour. Add the chilled eggnog and water, then stir until all dry ingredients are fully hydrated—you're looking for a shaggy, somewhat stiff dough. Let this mixture rest for 20-30 minutes (this is your autolyse period, which develops gluten naturally). I find this rest period makes the dough much easier to work with and improves the final texture.

Add the active sourdough starter to the hydrated dough from Step 1 and mix thoroughly for 1-2 minutes by hand or with a dough hook, ensuring the starter is completely incorporated. The dough will feel wet and sticky at this point—this is normal. Cover the bowl and let it rest for 30-60 minutes to allow the gluten network to begin developing. This rest period, called a rest phase, gives the flour time to fully absorb the liquid and the starter time to begin fermentation.

Sprinkle the salt over the dough from Step 2 and mix it in thoroughly—this can take 2-3 minutes by hand or with a dough hook. Salt strengthens gluten and controls fermentation speed. Once incorporated, cover the dough and set it aside for 1 hour at room temperature. This resting period allows salt to fully integrate and fermentation to continue building flavor. Then perform a series of stretch-and-fold movements: wet your hand, grab one side of the dough, stretch it up and fold it over itself, rotate the bowl 90 degrees, and repeat 4-6 times. This builds strength without aggressive kneading.

After the stretch-and-fold movements from Step 3, sprinkle the freshly ground cinnamon and freshly grated nutmeg over the dough. Gently fold these spices into the dough using the same stretch-and-fold technique—just 2-3 folds to distribute them evenly throughout. Cover the dough and let it continue fermenting at room temperature for another 1-2 hours, or until it has increased in volume by about 50% and shows visible air bubbles on the surface. I always use freshly grated nutmeg rather than pre-ground because the warm, aromatic oils make a noticeable difference in the final bread's flavor.

Turn the fermented dough from Step 4 onto a lightly floured surface and gently pre-shape it into a round by folding the edges toward the center. Let this rest for 15-20 minutes, then perform your final shaping by folding the edges toward the center again to create surface tension. Place the shaped dough seam-side up into a floured banneton proofing basket (or a bowl lined with a floured kitchen towel). Cover the basket and place it in the refrigerator for 8-14 hours. This long, cold proof develops deeper flavor through slow fermentation and makes scoring and handling the dough easier.

Preheat your oven to 475°F with a Dutch oven inside for at least 30 minutes—the hot vessel creates steam which develops a beautiful crust. Turn the cold dough from Step 5 out of the proofing basket onto parchment paper and score the top with a sharp knife or lame (a single 1/4-inch-deep slash works well). Carefully place the dough (still on parchment) into the preheated Dutch oven, cover with the lid, and bake at 475°F for 15 minutes to trap steam. This is where the eggnog and spices really shine—they caramelize slightly in the heat and create a complex, holiday-spiced crust.

After 15 minutes at 475°F, reduce the oven temperature to 450°F and remove the Dutch oven lid. Continue baking for 15 minutes, then rotate the Dutch oven for even browning. Bake for another 15-20 minutes until the crust is a deep golden-brown (almost mahogany in color). The total bake time should be around 45-50 minutes. Remove the bread from the oven and let it cool on a wire rack for at least 1 hour before slicing—this allows the interior crumb to set properly and makes slicing cleaner.