Sweet and Sour Chicken

3 c. boneless skinless chicken breasts, cooked and cubed
1/2 c. cider vinegar
1/3 c. ketchup
3/4 c. brown sugar
3 T cornstarch
1 1/2 c. chopped green pepper
20 oz. can drained pineapple tidbits
3 T. vegetable oil
Saute green pepper in vegetable oil until tender-crisp. In a small bowl, combine vinegar, cornstarch, ketchup, and brown sugar. Add to green pepper in hot pan and bring mixture to a boil. Stir until thickened. Removed for heat. Add pineapple and chicken. Serve over cooked rice.