Mix the marinade ingredients, add the beef, mix well and refrigerate again for at least 1 hour.
Mix the sauce ingredients and set aside with all the other ingredients near the stove.
Put a colander or stainless steel Chinese strainer over a pot and place near the stove. Heat a wok over high heat and add the oil.
When the oil is hot and almost smoking, add the beef. Stir and fry until it just changes color, then remove the beef with a slotted spoon and drain in the colander.
Heat the oil again until very hot. Return the beef to the oil and stir and fry once more, until the beef is crispy around the edges. Pour the beef and oil into the colander over the pot and allow the oil to drain away.
Reheat the wok to medium hot. Heat 2 tablespoons of the drained oil, then add the tangerine peel, chili peppers, ginger, garlic and scallion. Stir fry for a few seconds, or until the chili peppers brown, then add the beef. Stir for 30 seconds and add the sugar.
Add the sauce to the beef, stirring constantly until it coats the meat with a clear glaze. Turn off the heat and serve hot.