1 red chilli, finely sliced, plus extra slivers to garnish
1 green chilli, finely sliced
1 cinnamon stick
1 star anise
5 cm (2 inch) piece of fresh root ginger, peeled and thinly sliced
8 cm (3 inch) length of trimmed lemon grass stalk, finely chopped
400 ml (14 fl oz) hot fish stock
2 tablespoons fish sauce
1 tablespoon soft brown sugar
400 g (13 oz) raw peeled tiger prawns
6 baby pak choi, halved or quartered
400 ml (14 fl oz) can coconut milk
juice of 2 limes
250 g (8 oz) dried flat rice noodles (banh pho)
sliced spring onions, to garnish
Heat the oil in a saucepan, add the shallots, chillies, cinnamon stick, star anise and ginger and cook gently for 2 minutes. Add the lemon grass and stock and bring to a simmer.
Stir in the fish sauce, sugar and prawns and simmer for 5–6 minutes or until the prawns turn pink and are cooked through. Add the pak choi, coconut milk and lime juice and heat through until the pak choi wilts.
Cook the noodles according to the packet instructions, then drain. Divide the noodles into warm bowls and ladle over the pho mixture. Scatter with slivered red chillies and spring onions and serve immediately.