If using dried noodles, soak according to pack instructions. Cut the stalks off the coriander and finely chop them (set the leaves aside for later). Tip the chopped stalks into a mortar along with the garlic oil and ginger, then pound to form an aromatic paste.
Heat a wok and, when smoking, tip in the oil, then the paste. Cook for a few secs, then stir in the pepper and peas. Cook a few mins more until softened, then pour in the chilli.
Stir around the pan until cooked, then add the sugar, fish and oyster sauces. Drain the noodles, then add to the pan. Toss everything together, adding a little water if the noodles seem a bit dry. Just before serving, stir in the beansprouts and lime juice, then place on a serving plate and scatter over the roasted peanuts, spring onions and coriander leaves