My husband used to always request this for his birthday dinner. Although not truly authentic - it is not the red sauce more commonly seen - it is good n' easy, and also inexpensive - I originally copied it from an article on frugal dining. Served with rice and buttered ginger carrots, it is a simple - and tasty - meal.
Cut pork chops or tenderloin into bite-size pieces. Mix ginger with half of the flour. Coat pork pieces in the flour mixture. Brown in hot oil, removing pieces as they brown. Drain off excess oil, but leave a small amount with the pork drippings.
Mix remaining flour with 2/3 cup of water, then add vinegar and soy sauce. Add liquid to drippings in pan. Boil for 1 minute, stirring constantly. Stir in sugar; add pork.
Reduce heat, and simmer, covered, for 1 hour, or until meat is tender - *If using tenderloin, the cooking period will be greatly shortened, so don't overcook!
Add drained pineapple and bell pepper (if using). Simmer uncovered for 10 minutes.
Serve with steamed rice.
NOTE: You can add the pineapple juice in place of part of the water added in step 2 if you like; I don't because it makes it a little overly sweet for our tastes.