Put the ginger, garlic, soy and oil in a bowl with the sugar and stir until the sugar dissolves. Add the pork mix to coat in the marinade then leave to stand for at least 20 minutes. Cook the soya beans in a large pan of boiling water for 2 minutes, add the mange tout and cook for a further 2 minutes then add the pak choi and cook for 1 minute more, drain then cool under cold water, drain again and pat dry. Heat a drizzle of oil in a large non stick frying pan, shake any excess marinade off the pork then fry for 1 minute on each side, you may have to do this in batches. Return all the pork to the pan and pour in the remaining marinade, bubble for a few minutes then allow to cool to room temperature. Lay the vegetables on a platter, sprinkle over the spring onions then lay the pork on top and any juices and finish with the toasted cashews.
