Gaeng som pla - sour soup

This is a popular fish soup that is quite common in Thailand, where it 
is usually prepared using a local fish known as pla chon. However for 
the purpose of this recipe, I suggest using tinned herrings packed in 
brine. It can also be prepared just as succesfully using chicken and 
chicken stock (when it is known as gaeng som kai). 

If you can't find krachai (lesser ginger) then use ordinary ginger. 

--ingredients
-- 

about one and a half pounds of fish fillets. 

4 cups of fish stock 

3 tablespoons of chopped garlic 
3 tablespoons of chopped shallots 
3 tablespoons krachai (lesser ginger), thinly sliced 
3 tablespoons of mixed red and green prik chi fa (jalapenos), thinly 
sliced 
1 teaspoon kapi (shrimp paste) 
a quarter of a cup of fish sauce 
a quarter of a cup of tamarind juice 
1-2 tablespoons of palm sugar (to taste) 
2 cups of very coarsely chopped green vegetables 

--method
-- 

If you are using fresh fish then dehead, detail, and gut your fish and 
fillet it to produce four fillets of fish. 

Heat the stock to simmering point, and add all the ingredients except 
the fish and return it to the boil. 

Add the fish and simmer until the fish is cooked through. 

-- 

This dish can be eaten as a soup course, but as I have remarked before 
in Thailand soups are normally eaten with the other dishes of the 
dinner, rather than before them. Therefore you should use a slotted 
spoon to remove the fish and serve it in individual bowls to the diners, 
the soup liquor is then placed in a large serving bowl, from where they 
can help themselves (you can use a fire pot of fondue cooker to keep it 
hot if you wish).