01 - Pat the chicken thighs thoroughly dry with paper towels. Season both sides generously with salt and pepper. Lightly dredge each thigh in flour, shaking off any excess to ensure an even, thin coating.
02 - Heat the olive oil in a large Dutch oven or heavy-bottomed pot over medium-high heat until shimmering. Working in batches to avoid crowding, sear the chicken thighs until deeply golden on both sides, approximately 4 minutes per side. Transfer the browned thighs to a plate and set aside.
03 - Reduce the heat to medium. In the same pot with the rendered drippings, add the diced onion, carrots, and celery. Sauté, stirring occasionally, until the vegetables are softened and just beginning to caramelize, about 5 to 6 minutes. Add the minced garlic and continue cooking for 1 minute until fragrant.
04 - Pour in the dry white wine, using a wooden spoon to scrape up any browned bits from the bottom of the pot. Allow the wine to reduce by roughly half, about 2 to 3 minutes, concentrating the flavor.
05 - Stir in the diced tomatoes with their juices and the chicken stock. Add the dried thyme and bay leaf. Nestle the seared chicken thighs back into the pot, skin-side up, pouring over any accumulated juices from the plate. Bring the liquid to a gentle simmer.
06 - Cover the pot with a tight-fitting lid and reduce the heat to low. Braise for 1 hour, stirring gently once or twice to prevent sticking, until the chicken is fall-off-the-bone tender and the sauce has developed rich flavor.
07 - Remove the lid for the final 15 minutes of cooking to allow the sauce to reduce and concentrate further. Adjust the consistency to your preference by allowing more or less reduction time.
08 - Remove the pot from the heat. Discard the bay leaf. Stir in the fresh lemon zest and chopped parsley. Taste the sauce and adjust seasoning with additional salt and pepper as needed. Ladle into shallow bowls over creamy polenta, whipped mashed potatoes, or alongside crusty bread to soak up the sauce.