The Vietnamese do a broth of clams, basil and carambola, or starfruit. This sprightly take on a tom yam soup raps on that terrific idea. Because starfruit is, flavour-wise, crisp and clean, it lends a light, grassy balance. If you have a ripe fruit, you can use less sugar. Taste as you go.
For the broth
3 inch knob of each ginger and galangal, roughly sliced
3 lemongrass stalks, roughly chopped
4 bird's eye chillies, finely sliced
6 lime leaves, roughly torn
2 whole coriander bundles, bruised
1 teaspoon white peppercorns
2 - 3 tablespoons fish sauce
1 - 2 tablespoons caster sugar
The juice of a large lime
Bring a litre of water to a simmer. Drop in everything but the fish sauce, sugar and lime juice. Cover with a lid and leave to simmer for about 20 - 30 minutes or till the wafting fumes are fragrant. Remove the solid aromatics from the saucepan and season with the fish sauce, sugar and lime juice.
To finish off
1 starfruit, thinly sliced
A handful of tiger prawns, with just their tails on
2 squids, opened and cleaned
Slit the prawns' spines and scrape out any black material. Score the cleaned, opened squid tubes tubes criss-cross and slice into 1 cm strips. Keep the bundle of arms whole, just trim the two tentacles.
Simmer stock and add the prawns. As they turn coral and foetal, slip in the squid and starfruit slices. The squid curls into bouncy blossoms very quickly and when they do, there is absolutely nothing to do but ladle them out.
Strew finely-shredded lime leaves over the top. A flutter of whole coriander leaves is a nice touch, too. Or, if you're adamant about some serious spiciness, add more finely sliced chillies.
