Tear off the fat from the chicken cavity
and discard. Cut off the parson's nose and rinse the chicken in cold
water. Bring a large pot of water to the boil over high heat and plunge
in the chicken. When the water comes to the boil again, let the chicken
cook for 1 minute to firm the skin. Remove it and rinse it briefly with
running warm water to get rid of any scum.
Bring the measured amount of water to the
boil with the ginger slices and Nuoc Mam sauce in a deep pot into which
the chicken will fit snugly.
Add the chicken and, when the water boils
again, turn the heat down to a simmer.
Cover and simmer for 1 1/2 hours, turning
the chicken from time to time to ensure that it cooks evenly.
In the meantime, soak the black mushrooms
in some warm water for about 20 minutes. Squeeze them dry and rinse in
cold water, repeating this a couple of times. Cut off and discard the
stems and add the mushrooms to the soup about 30- minutes into the
cooking time. Add the sherry when the chicken is cooked and season with
salt to taste.
Serve the chicken whole in the soup and
dips in individual saucers. Guests tear off pieces of the meat with a
fork or chopsticks and put it in their bowls with a little broth and
Leftover chicken can be used for a variety