Soak the black wood ear fungus for 10
minutes or until soft in nearly boiling water. When soft, slice
thinly and place in stock. Add the button mushrooms to the stock if
using those instead.
Put into a dish and place on the table.
Slice the cucumber into thin rounds or cut
into fine matchsticks. Place in a dish and put on the table.
Soak the vermicelli in water that has been
boiled and allowed to cool slightly (above 5 minutes). Drain and place
in four bowls.
Place the shrimps in a bowl and put on the
table. Meanwhile, boil and simmer the stock.
The guests garnish their bowls with the
ingredients in the dishes placed on the table, then pour the hot stock
over the whole.
The Nuoc Mam sauce is added to taste and
the soup bowls are garnished with the unpeeled shrimps.