Slice the beef into thin slices about 4cm long.
Put slices into a bowl and add the marinade ingredients. Stir well and leave for at least 15 minutes to marinate.
Heat a wok until very hot, add oil until smoking, then take the beef from the marinade and stir fry for about 2 minutes, Remove from the wok and set aside.
Reheat the oil in the wok and stir fry the onion, garlic & ginger for another couple of minutes.
Add the remaining ingredients & mix thoroughly. Turn down the heat, cover and simmer for about 15 minutes.
Add the meat back to the wok and stir well to reheat.
Serve scattered with fresh coriander.