Roasted Garlic Rosemary Country Sourdough Boule

Steps

1. Morning, day 1: feed your sourdough starter at its usual 1:1 ratio and leave it at about 75°F (24°C) for 4 to 6 hours, until doubled, domed and bubbly; it is at its peak when a spoonful floats in water.
2. About 1 hour before the starter peaks, heat the oven to 400°F (200°C). Toss the garlic cloves with the olive oil in a small oven-safe dish, cover tightly with foil and roast 25 to 30 minutes until soft and golden. Cool, then roughly chop the garlic.
3. Also while the starter rises, mix the bread flour and whole wheat flour with 340 g of the water (all but 20 g) until no dry patches remain. Cover and rest 1 hour (autolyse).
4. Add the peaked sourdough starter to the dough and squeeze it in with wet hands until even. Sprinkle the salt over the dough with the remaining 20 g of water and squeeze and fold until absorbed. Counting the starter, this dough is about 75% hydration and 2% salt.
5. Bulk rise at about 75°F (24°C) for 4 to 5 hours. After the first 30 minutes, stretch the dough out on a damp counter, scatter the rosemary and the roasted garlic over it, roll it up and return it to the bowl.
6. Do 3 more sets of stretch-and-folds, 30 minutes apart: with wet hands, lift each side of the dough and fold it over the middle. Then leave the dough untouched until it has grown about 50%, looks domed and jiggly, and shows bubbles at the sides.
7. Turn the dough onto a lightly dampened counter, pre-shape into a loose round and rest 20 minutes uncovered. Shape into a tight boule, building surface tension, and place it seam side up in a parchment-lined bowl.
8. Cover and cold proof in the fridge for 12 to 16 hours overnight.
9. Day 2: place a lidded Dutch oven in the oven and preheat to 500°F (260°C) for 45 minutes. The dough is ready when a wet fingertip dent springs back slowly.
10. Turn the cold boule onto parchment, score a deep cross or curved slash, and lower it into the hot Dutch oven. Cover, reduce to 475°F (245°C) and bake 20 minutes.
11. Uncover, reduce to 450°F (230°C) and bake 22 to 28 minutes more, until the crust is a deep mahogany brown and the center reads 205 to 210°F (96 to 99°C).
12. Cool the loaf on a rack for at least 2 hours before slicing into 12 slices.