Heat the Oven - Set the oven rack to the lower third position. Preheat to 350ºF (177ºC).
Prepare the Chicken - Trim any excess fat or skin from the chicken thighs. In a small bowl, combine 1 teaspoon salt and ½ teaspoon pepper. Generously season both sides of the chicken.
Sear the Chicken - Heat a large 12-inch oven-proof skillet or dutch over medium-high heat. Add 1 tablespoon olive oil. Once hot, carefully add in the chicken thighs, skin-side down. Sear for 5 minutes until crispy and browned. Flip and cook for 2 minutes, turn off the heat. Transfer to a clean plate, leave 2 tablespoons of the fat drippings in the pan. Alternatively, drain the drippings and add 2 tablespoons of olive oil to the pan.
Cook the Vegetables - Heat the skillet over medium heat. Add the onions, garlic, and Italian seasonings. Saute for 2 minutes until the onions are crisp-tender. Add the red and green bell peppers, saute for 1 minute. Add the tomato paste and saute for 1 minute.
Add the Wine - Add the wine, stir and simmer until almost completely evaporated, about 1 to 2 minutes.
Add Tomatoes, Capers, and Mushrooms - Stir in the crushed tomatoes, diced tomatoes with the juice, chicken broth, and capers. Stir in the mushrooms.
Cook the Chicken - Add the chicken back to the pan, turn to coat in the sauce, and leave it skin-side facing up, simmer for 5 minutes. Cover the skillet with a lid and carefully transfer the pot to the oven. Cook until the meat is very tender, about 60 minutes. Season sauce with salt and pepper to taste.
To Serve - Garnish the chicken cacciatore with parsley and basil, serve hot.
Notes
Using Chicken Breasts: Check the chicken after 10 minutes of braising, and then every 5 minutes after, until the internal temperature reaches 160 to 165ºF (71 to 74ºF).
Using Red Wine: Use a dry red wine like Chianti or pinot noir.
Stovetop Braising: After simmering the sauce for 5 minutes, cover and reduce heat to low. Stir the sauce every 10 minutes to prevent burning on the bottom of the pan. Cook until the meat reaches 170ºF (77ºC).
For a Thicker Sauce: Transfer the chicken to a serving platter, cover with foil to keep warm. Heat the sauce over medium-high heat, stir and cook until the sauce reduces to the desired consistency.
For a Spicy Sauce: Add ⅛ to ¼ teaspoon of red pepper flakes when sauteing the Italian seasonings in the fat.
Storing: Store in an airtight container for up to 5 days in the refrigerator.