1.5 cm (¾ inch) piece of fresh root ginger, peeled and cut into matchsticks
1 small red chilli, thinly sliced
2 heads of pak choi, sliced in half lengthways
150 g (5 oz) ramen or egg noodles
coriander leaves, to garnish
Place the oil in a large frying pan over a medium heat and fry the salmon fillets, skin-side down, for 3–5 minutes, until the skin is really crispy. Turn carefully and cook for a further minute, until still slightly rare. Transfer to a plate and keep warm.
Pour the stock into a saucepan, add the lime juice, fish sauce, soy sauce and ginger and bring to the boil. Simmer for 3–4 minutes, then add the chilli and pak choi and simmer for another 4–5 minutes, until tender.
Meanwhile, cook the noodles in a pan of boiling water for 2–3 minutes, or according to the packet instructions, until just tender. Drain and heap into bowls.
Ladle over the hot broth and top each bowl with a salmon fillet. Serve immediately, garnished with coriander leaves.