Serves 4 to 6

This is the quintessential Thai soup that many Europeans love to order in Thai restaurants. The word 'Tom' in Thai translates as 'boiling water cooking' and in Thailand this soup would be brought to the table at the same time as the rice, curries and other dishes and eaten intermittently as a kind of palate refresher.

Kaffir lime leaves are an intensely perfumed herb that is indispensible in Thai cooking. One of the best places to buy Thai ingredients is the New Loon Moon supermarket in Chinatown. The lime leaves are also sometimes available from Turnips at Borough Market.

If you can't find the coconut cream, you can scoop the thick white coconut cream from the top of a tin of coconut milk that has separated.

Ingredients

1 litre of coconut milk
400 grams of chicken breasts, sliced into bite-sized pieces
2 stalks of lemongrass, tough outer layers removed and sliced on the diagonal
Two 2 inch pieces of galangal, sliced
2 stalks of coriander including roots
5 Kaffir lime leaves, torn in half
4 tbsp fish sauce
A handful Straw, Shitake or button mushrooms, halved
125 mls coconut cream
5 tbsp lime juice
3 Thai bird's eye chilies, sliced in half lengthwise

Instructions

Place the coconut milk, chicken, lemongrass, galangal, coriander roots (reserve the leaves for garnishing), and lime leaves in a medium-sized pot and bring to a boil. Simmer for 10 minutes.

Add the fish sauce, mushrooms and coconut cream. Stir well and return to a boil, then remove from the heat.

Stir in the lime juice, chilies and reserved coriander leaves and taste. Adjust with more lime, fish sauce, chili and coriander until the right balance of spicy, salty and sour are reached.

Serve hot.