In a bowl mix the rice wine vinegar, soy sauce, sesame oil, marmalade, brown sugar, salt and pepper. Set aside.
In a plastic self sealing bag, add the cornstarch and chicken. Shake to coat. Pour vegetable oil in the skillet and brown the sides of the covered chicken.
When chicken is browned on all sides, place pieces into the slow cooker. Then cover the chicken with the sauce mixture gently stir to coat chicken pieces.
Cook on low 4-5 hours or high 2-3 hours. Garnish with sesame seeds and sliced green onions.
Serve with Ling Ling Fried Rice.