First, put the stock, lemon grass, lime leaves and ginger in a large pan. Bring to the boil, stirring.
Now add the coconut milk, chicken, fish sauce and sugar and simmer until the chicken slices are tender, about 5-10 minutes.
Put the lime juice and chilli paste in the base of a large serving bowl. Mix them together. Pour the hot soup on top and sprinkle with the coriander and chillies.
© 1994 Keith Floyd estate. All rights reserved.