Heat oil in a Dutch oven and brown chicken pieces on all sides.
Mix together soy sauce, brown sugar, water, ketchup, sherry, red pepper, garlic and green onion. Pour mixture over chicken. Cover and simmer 35 to 40 minutes.
Remove chicken to platter, draining juices that accumulate back into pan. Skim off fat from sauce.
Blend together cornstarch and water, stir into sauce. Cook, stirring constantly, until thickened. Spoon some sauce over chicken, sprinkle with sesame seeds. Serve chicken with remaining sauce.
*Sesame seeds need to be toasted to develop their nut-like flavor. Toast sesame seeds in a shallow pan at 350° F for about 10 minutes, stirring frequently.Servins: 4