Pre-heat the oven to 375 degrees F. Season the chicken on both sides with salt and pepper. In a large skillet or Dutch-oven, heat the oil and brown the chicken, skin-side down for about 7-8 minutes. Brown the chicken in batches as crowding the pan will cause the chicken to steam and not brown. Transfer the browned chicken thighs to a large baking dish. Scatter the artichokes hearts (not the brine), olives, garlic, lemon slices and thyme sprigs over the chicken, and set aside.
Pour off and discard the fat from browning the chicken, but save the browned bits at the bottom of the pan. Add a couple of tablespoons of the artichoke brine (if available), chicken broth, sherry and fish sauce or soy sauce, and bring to a boil. Pour this mixture around the chicken in the baking dish. Cover tightly with aluminum foil and braise the chicken for about one hour, or until the internal temperature reaches 165 degrees F, using a meat thermometer.
Increase the oven temperature to 400 degrees F. Uncover the chicken and continue to cook for 5-10 minutes longer to crisp the skin. Discard the thyme leaves and serve the chicken with the pan sauce. Finish with a squeeze of fresh lemon juice.