Chicken and Biscuits

Ingredients

• 2 tablespoons vegetable oil
• 1½ lb lb. skin-on, bone-in chicken thighs
• Kosher salt and freshly ground black pepper
• 8 medium carrots (about 1 lb.), peeled, cut into 2” pieces
• 1 small celery root (about 12 oz.), peeled, cut into ½” pieces
• 1 medium onion, chopped
• 1 leek, white and pale-green parts only, chopped
• ¼ cup (½ stick) unsalted butter
• ¼ cup all-purpose flour
• 1 cup dry white wine
• 4 cups low-sodium chicken broth
• 4 sprigs thyme
• 1 sprig rosemary
• 2 bay leaves
• 1½ teaspoons (or more) Sherry vinegar
• 2¼ cups all-purpose flour plus more for work surface
• 2 teaspoons kosher salt
• ¾ teaspoon baking powder
• ½ cup (1 stick) cold unsalted butter, cut into ½” cubes
• ¾ cup buttermilk
• 2 tablespoons crème fraîche or sour cream
• 2 tablespoons chopped fresh chives
• 1 large egg, beaten to blend

Steps

1. Preheat oven to 400°. Heat oil in a large pot over medium-high heat. Season chicken with salt and pepper. Cook skin side down until skin is golden, 8–10 minutes; transfer to a plate.
2. Carefully drain all but 2 Tbsp. fat from pot. Add carrots, celery root, onion, and leek; stir frequently until softened and beginning to brown, 8–10 minutes.
3. Add butter; stir until melted. Add flour and stir constantly until well blended, about 2 minutes. Add wine and ½ cup water. Bring to a boil; reduce heat and simmer until liquid is reduced by half, 5–8 minutes.
4. Add chicken, broth, thyme, rosemary, and bay leaves. Bring to a boil; reduce heat. Simmer until chicken is fork-tender, 35–40 minutes. Discard herb sprigs and bay leaves. Transfer chicken to a plate. Let cool slightly; shred meat, discarding skin and bones.
5. Return shredded chicken to soup. Add 1½ tsp. vinegar. Season with salt, pepper, and more vinegar, if desired. DO AHEAD: Soup can be made 2 days ahead. Let cool slightly; chill until cold. Cover and keep chilled. Reheat before serving.
6. Whisk flour, salt, and baking powder in a large bowl. Add butter. Using your fingertips, blend until pea-size lumps form. Add buttermilk, crème fraîche, and chives. Using a fork, mix until just combined. Gather mixture into a ball and knead in bowl just until a shaggy dough forms, 3 or 4 times.
7. Transfer dough to a floured work surface and pat into a ¾”- to 1”-thick round. Cut out rounds with a 2” biscuit cutter or small glass. Gather dough and repeat patting and cutting. Transfer to a parchment-lined rimmed baking sheet; brush with egg.
8. Bake biscuits until golden brown, 25–30 minutes. Serve warm or at room temperature. DO AHEAD: Biscuits can be made 8 hours ahead. Let cool completely and store airtight at room temperature.
9. Divide soup among bowls and top with biscuits.