Place the prawn
meat and diced fish or squid in a food processor or
blender with chopped white onions and garlic and
process to a smooth paste.
Add salt and
pepper, egg white and cold water and process again
until the mixture is smooth and light. Use wet or
oiled hands to form into small balls.
Bring a large pan
of water to the boil, salt lightly and poach the
seafood balls until they float to the surface. In
the meantime soak the vermicelli or noodles in warm
water to soften.
Bring fish stock
to the boil, add drained noodles and simmer until
tender. Add fish sauce to taste. Divide the seafood
balls between six large soup bowls and add two crab
legs to each and a few sprigs of coriander. Add the
soup and noodles.