1. Season fish with salt and pepper. Dredge in flour. Deep-fry in oil until crispy.
2. In a separate pan, heat the oil. Sauté onions for 1 minute. Remove from the pan and set aside.
3. Add the vinegar, ketchup, reserved pineapple syrup, soy sauce, and sugar. Simmer while stirring continuously until thick.
4. Add the DEL MONTE Pineapple Tidbits and onions. Pour over fried fish. Serve.