Rinse pork, drain in colander for 10-15 minutes and then pat dry it with a paper towel
Cut pork into preferred bite size (approx. 1”x1”x2”)
Preheat a wok WITHOUT oil for pork belly OR preheat wok with oil for pork shoulder butt for a few minutes
Put all pork into wok and let it brown for a minute or two on one side, oil will come out from the pork belly, and the pork belly will become golden, then flip and let it brown, in the mean time, add a piece of ginger and continue to let it brown
After browning the pork for a few minutes, add brown of sugar to the meat and keep stir frying until all the sugar are melted (see pic)
Then add soy sauce, dark soy sauce and water, bring it to a boil, then simmer in medium low heat for about 20 minutes or until it is tender (add “old” sauce now if you have any, see tips #2 below)
Salt to taste if needed
Add vinegar and mix well, serve with rice