For the pork
450g/1lb pork fillet
1½ tbsp groundnut oil
1 tsp garlic infused oil
3 tbsp coarsely chopped fresh coriander
1 tbsp dark soy sauce
2 tsp sugar
225g/8oz fresh or tinned pineapple, chopped
For the marinade
2 tsp light soy sauce
2 tsp Shaoxing rice wine or dry sherry
1 tsp sesame oil
2 tsp corn flour
For the garnish
handful fresh coriander sprigs
Cut the pork into thin strips about 5cm/2in long. In a medium bowl, combine the marinade ingredients. Add the pork, mix well and leave to marinate at room temperature while you prepare the other ingredients. Drain, discarding the marinade.
Heat a wok over a high heat until it is hot. Add the oil, and when it is very hot and slightly smoking, add the pork and stir-fry for 3 minutes.
Finally, add the pineapple, coriander, soy sauce and sugar and continue to stir-fry for 3 minutes.