Cut pork tenderloin into cubes
Cut green pepper, red pepper, and onion into chunks.
Combine pork, pineapple, pineapple juice, peppers, onion, vinegar, ginger, soy sauce and brown sugar in slow cooker.
Cook on low for 6-8 hours.
About 5 minutes before serving, mix cornstarch and water in small bowl. Add to slow cooker and stir into pork mixture. Cover and cook on high for 5 minutes or until sauce thickens.
Serve over rice.