Toasted Pecan Whole Wheat Sourdough Focaccia

Steps

1. Day 1, morning: feed your sourdough starter its usual 1:1:1 meal by weight and leave it at about 75°F (24°C) for 4 to 8 hours, until it has doubled, is domed and bubbly, and a spoonful floats in water.
2. While the starter rises, toast the pecans in a dry skillet over medium heat for 4 to 5 minutes, stirring, until fragrant; cool. Coarsely chop about 60% of the pecans for the dough and roughly break the remaining 40% for the topping; keep them separate.
3. When the starter peaks, mix the whole-wheat flour, the bread flour and all but about 30 g of the water in a large bowl until no dry patches remain. Cover and rest 45 minutes (autolyse).
4. Add the sourdough starter to the dough and squeeze it in with wet hands. Sprinkle on the salt and the reserved water and squeeze and fold until fully absorbed. Then add one quarter of the olive oil and work it in. The dough is about 82% hydration and 2% salt, counting what the starter contributes.
5. Bulk rise at about 75°F (24°C): cover and rest 30 minutes, then do a set of stretch-and-folds, lifting one side of the dough and folding it over, turning the bowl four times. Repeat for 4 sets 30 minutes apart, scattering the chopped pecans for the dough over the dough before the second set and folding them in.
6. After the last fold, leave the dough covered until it has grown about 50%, looks domed and jiggly, and shows bubbles on the sides, about 3 to 4 hours from mixing in the starter.
7. Pour half of the olive oil into a 9x13-inch metal pan and spread it over the bottom and sides. Tip the dough into the pan, turn it once to coat, and gently stretch it toward the corners; if it springs back, rest 15 minutes and stretch again.
8. Cover the pan and cold proof in the fridge overnight, 12 to 16 hours.
9. Day 2: take the pan out and let the dough warm at about 75°F (24°C) for 2 to 3 hours, until it fills the pan, is puffy and bubbly, and springs back slowly when poked.
10. Preheat the oven to 450°F (230°C) with a rack in the lower third for at least 30 minutes.
11. Drizzle the remaining quarter of the olive oil over the dough, then dimple it all over with oiled fingertips, pressing to the bottom of the pan. Scatter the broken pecans for the topping over the dough and press them lightly into the dimples.
12. Bake 25 to 30 minutes, until deep golden on top and crisp and browned underneath, and the center reads 205°F (96°C).
13. Slide the focaccia out of the pan onto a wire rack right away so the bottom stays crisp, and cool at least 30 minutes before cutting into 12 slices.