16 raw shell-on king prawns
1.5 litres water
pack of fish balls (available in any Chinese supermarket) – optional
1-2 squid, prepared as for Thai squid salad
Dash of oil
6 lime leaves, roughly torn
2 lemongrass stalks, cut into 5cm pieces and crushed
2 slices galangal
2 bird’s eyes chillies, finely sliced
1 tbsp palm sugar
Juice of 1½ limes
2 tbsp fish sauce
handful of shitake, enoki or small round Thai mushrooms (like champignons) mushrooms
6-8 cherry tomatoes (optional, I don’t add them as I’m not supposed to eat them)
Handful of coriander or Thai basil leaves, torn, to serve
1/2 tsp of Nam Prik Pow for extra flavour and heat

 Shell the prawns, keeping the head, and set the meat aside. Heat the oil in a pan on a medium-high flame, and fry the shells until pink. Add 1 litre of water and simmer for 15 minutes, then strain and discard the shells.

To prepare the squid, slit down one side and open out. Then, with a sharp knife, score the flesh in a criss-cross pattern, without quite cutting right through it. This is not only pretty when cooked but also allows the squid to curl attractively. Then cut each scored squid into 1 inch/25 mm slices.

Return the prawn stock to a clean pan, and add 2 of the lime leaves, lemongrass and galangal. Bring to a simmer and leave to infuse for 10 minutes, then add the chillies and simmer for another couple of minutes.

Add the mushrooms, tomatoes, remaining lime leaves, squid, fishballs and prawns, and cook through until pink. Take off the heat and stir in the sugar, lime juice and fish sauce. Add the Nam Prik Pow if you want to really acme it fiery! Taste for seasoning, and then pour into bowls. Garnish with coriander or basil and serve immediately.

Option: if you want a more substantial soup, add some rice vermicelli noodles, pre-soaked in hot water, at the end. Then it’s a meal in a bowl.