Soak the black fungus in plenty of boiling water. Leave aside.
Prepare the vegetables and chicken. (Note 1)
In a stock pot (5 L - 6 L), bring 2.5 L of water to the boil and add the whole chicken breast side down. Allow the chicken to boil vigorously for 5 mins and spoon up all the scum that accumulates on the surface. (Note 2)
Turn down the heat to medium low and add the salt, pepper, sugar and all the vegetables to the stock pot. Continue to simmer on a medium - low heat for 45 minutes. Remove any visible scum build up on the surface of the soup.
After 45 minutes, turn off the heat and leave with the lid on for 10 minutes. Remove the chicken from the pot and check the chicken is cooked. If not, pop it back into the pot and cook until done. (Note 3)
Strain the soup and press out as much liquid from the vegetables as you can. Afterwards, keep the soup pot on low heat with the lid on. (This stepped can be skipped if serving the vegetables with the soup)
Drain the shredded black fungus and boil it in plenty of water in a separate small pot for 10 minutes. Then scoop the fungus out and set it aside for assembly.
Add 3 tbsp of fish sauce to the soup and check the seasoning. Adjust according to you taste. If here is too much fat floating on the surface, scoop it out with a spoon. (Note 4)