Preheat oven to 350°F. Sprinkle chicken with salt and pepper. Heat 2 tablespoons oil in heavy large skillet over medium-high heat. Add 3 chicken breasts, skin side down; sauté until skin is brown, about 3 minutes. Transfer chicken, skin side up, to 15x10x2-inch glass baking dish. Repeat with remaining chicken. Heat remaining 2 tablespoons oil in same skillet over medium-high heat. Add mushrooms, onions and bell pepper. Sauté until vegetables are tender and mushrooms begin to brown, about 12 minutes. Add wine; boil 2 minutes. Add broth and seasoning mix and bring to boil. Pour sauce over chicken. Cover dish with foil. Bake chicken 25 minutes. Uncover and bake until chicken is cooked through and sauce thickens, about 15 minutes longer. Serves 6. A very special thanks to a Bon Appetit for this great recipe!