Combine pork with the marinade ingredients in a large bowl, cover and leave to marinate in the fridge for 30 minutes or overnight.
Heat 2 tbsp of the oil in a hot wok until the surface seems to shimmer slightly. Add half the marinated pork and stir-fry for 30 seconds. Remove from the wok with a slotted spoon and set aside; heat the remaining oil in the work and add the remaining pork and stir-fry for 30 seconds.
Return the reserved pork to the wok with the spring onions, vinegar, soy sauce, water and lime halves. Stir fry a further minute or until the pork is cooked through and slightly browned.