Season both sides of the chicken thighs with salt and black pepper.
Heat the avocado oil in a large thick-bottomed pot (such as a Dutch oven) over medium-high heat. Allow the pot to heat up for a few minutes until it is sizzling hot. Place the chicken thighs in the pot in a single layer, skin side down and brown for 4 to 6 minutes, until the chicken skin is deeply golden brown.
Carefully flip and sear for another 2 minutes. Note: this will likely need to be done in two batches as there won’t be enough room to brown the chicken all at the same time.
Transfer the chicken to a plate and set aside.
Add the onion to the pot and sauté, stirring occasionally, until it begins to soften, about 5 minutes, scraping the browned bits off the bottom of the pan while sautéing.
Stir in the bell pepper, mushrooms, and garlic and continue sautéing, stirring frequently, for another 3 to 5 minutes. Add in the Italian seasoning, fresh sage, paprika, sea salt, diced tomatoes and red wine and stir well.
Transfer the chicken back to the pot, maneuvering it around until it is fully submerged in liquid. Cover the pot and bring it to a full boil. Reduce the heat to a simmer and continue cooking for 35 to 50 minutes (I do 40), until the chicken is nice and tender. Taste the sauce for flavor and add more sea salt to taste.
Serve the chicken over rice, noodles, zucchini noodles, or cauliflower rice with plenty of sauce and fresh grated parmesan cheese and fresh basil.