1.Cut the mange tout in half. Cut the beef into 2.5cm dice. Mix with the marinade ingredients and 30g of water and set aside for 20 minutes.
2.Heat some oil in a wok and stir fry the beef until just cooked through. Remove and set aside. Stir fry the mange tout and peppers. Remove and set aside.
3.Heat a little more oil in the wok. Add the black beans, black garlic, dried chillies, ginger, garlic, and scallions, and stir fr y until fragrant. Return the beef and vegetables to the wok and add the oyster sauce, sugar, and salt, and cook for a few minutes to reduce the sauce.