¼ cup potato starch
½ tablespoon ginger juice, squeezed from grated ginger
½ tablespoon soy sauce
1 tablespoon rice vinegar
1 tablespoon Shaoxing wine
1 tablespoon soy sauce
2 tablespoons black vinegar
2 tablespoons Shaoxing wine
2 tablespoons unrefined sugar
450 grams (1 pound) pork, cut into bite-size pieces
Put the pork into a bowl along with 1 tablespoon of Shaoxing wine, the soy sauce and ginger juice. Stir to combine and allow it to marinate for 1 hour.
When the pork is done marinating, add 1" of oil to a heavy bottomed pot and preheat the oil to 340°F (170°C). Prepare a wire rack by lining it with several layers of paper towels.
Put the potato starch in a small bowl, and roll each piece of pork in it to give each piece an even coating of starch.
Fry the pork in batches (depending on how big your pot is) until lightly browned and cooked though. Transfer the fried pork to the paper towel lined rack.
In a sauté pan, add the remaining Shaoxing wine along with the black vinegar, rice vinegar, soy sauce and sugar. Turn the burner on to high heat and bring the mixture to a boil.
Add the pork, into the black vinegar sauce, and continue boiling until the sauce is very thick and syrupy and coats each piece of pork, rather than the pan. Serve with steamed rice.