In a large saucepan, place the chicken, ginger, onions, and coriander. Cover with water. Bring to a boil and simmer gently for about 3 hours, uncovered. Add the fish sauce. Remove the chicken from the broth. Remove the legs and cut in two pieces. Remove the bones from the chicken breasts and cut them into pieces. Strain the broth through a sieve and adjust the seasoning.
Garnish
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