Trim extra fat from the chicken and rinse under cold running water and pat dry. Rub all over with 2 teaspoons salt, including inside the cavity.
In a large pot, add enough water (about 3 litres) to cover the chicken. Add the ginger, garlic, spring onions and remaining salt. Bring to a boil.
Gently lower the chicken into the stock and bring back to a boil. Reduce the heat to low and simmer for another 15 minutes, skimming off any scum. Cover and turn off the heat. Let chicken sit in the pot for about 1 hour and 20 minutes.
Poke chicken in the thigh using a chopstick. If the juices run clear, chicken is done. If the chicken isn't done, return it to the pot and simmer over low heat for a few more minutes. Carefully remove chicken from the stock and drain.
Transfer chicken to a chopping board and allow to cool slightly. Rub sesame oil over the chicken before using a cleaver to cut through the bone into small pieces.
Serve with chilli sauce or red vinegar.
Since this is such a simple dish, make sure you buy the freshest, tastiest chicken you can find.