Pour 3 tablespoons of the chicken stock
over the fish. Place in a heatproof dish and steam until tender, about
10 minutes.
To make the sauce, combine the remaining
chicken stock, garlic, chilies, lime juice, fish sauce, tamarind juice,
sugar and salt in a wok or saucepan.
Bring to a boil over high heat. Reduce
heat to medium and simmer for 1 to 2 minutes until the sauce is
thickened. It should taste sour, sweet and salty.
Pour the sauce over the steamed fish and
garnish with spring onions and slices of lime.