In a large Dutch oven or heavy pot, heat the olive oil over medium-high heat. Season the chicken thighs with salt and pepper, then add them to the pot. Brown the chicken on both sides, about 5 minutes per side. Remove the chicken and set aside.
In the same pot, add the diced onion, carrots, and celery. Sauté for about 5 minutes until the vegetables are softened. Stir in the minced garlic and cook for an additional minute.
Pour in the white wine, scraping the bottom of the pot to deglaze. Allow it to simmer for 2-3 minutes until slightly reduced.
Add the diced tomatoes (with their juices), chicken broth, thyme, oregano, bay leaf, and the browned chicken thighs back into the pot. Bring to a simmer.
Cover the pot and reduce the heat to low. Let it cook for about 1 hour, or until the chicken is tender and easily pulls apart with a fork.
Remove the bay leaf and stir in the lemon zest. Adjust seasoning with salt and pepper as needed.
Serve the chicken osso bucco hot, garnished with fresh parsley.
Notes
For a richer flavor, add a tablespoon of tomato paste when sautéing the vegetables.
Serve over creamy polenta or mashed potatoes for a heartier meal.