01 - Pat the chicken thighs and drumsticks dry with paper towels. Season both sides generously with salt and freshly ground black pepper.
02 - Heat olive oil and butter in a large sauté pan or Dutch oven over medium-high heat. Once the butter is foaming, place the chicken skin-side down and sear until deeply golden brown, about 5 minutes per side. Transfer the chicken to a plate and set aside.
03 - In the same pan with the rendered drippings, sauté the chopped onion for 3–4 minutes until soft and translucent. Add the minced garlic and sliced mushrooms, continuing to cook until the mushrooms have released their moisture and are lightly browned.
04 - Stir in the tomato purée and cook for 1 minute to deepen its flavor. Pour in the dry white wine, scraping up any browned bits from the bottom of the pan. Let the wine simmer for 2 minutes to reduce slightly.
05 - Add the diced tomatoes with their juices, chicken stock, thyme, and bay leaves. Nestle the seared chicken pieces back into the pan, skin-side up. Bring the liquid to a gentle simmer.
06 - Cover the pan with a tight-fitting lid and reduce the heat to low. Cook for 30 minutes, allowing the chicken to braise and become tender in the sauce.
07 - Remove the lid and continue simmering uncovered for 10–15 minutes, until the sauce has thickened and coats a spoon. Confirm the chicken is cooked through (internal temperature of 165°F).
08 - Discard the bay leaves. Transfer the chicken and sauce to a warm serving platter and sprinkle generously with chopped fresh parsley. Serve alongside mashed potatoes, crusty bread, or buttered noodles.