Trim the skin & fat off of the chicken with scissors. Let chicken sit in cold water for 30min.
Prep aromatics: whole onion, scallion roots, whole garlic, peppercorn and ginger and put them inside a simmering pouch.
Add chicken & simmering pouch into the Instant Pot. Fill water to the max line. Select 'Pressure Cook' button/high pressure and set timer for 1hour with sealed valve. After one hour, keep valve sealed, keep in warm mode for 20min. Release vent.
Twist lid off and gently discard simmering pouch. Skim fat with ladle. Pick up chicken carefully and place in a separate bowl.
Select 'Saute' mode on Instant Pot. When stock boils, add seasoning for the broth: salt, pepper, soy sauce, minced garlic, sliced onion, chopped scallions and boil for a 1min. Turn off Instant Pot.
Place chicken in middle of the bowl and pour generous amount of hot broth on top. Can garnish with sesame seeds and chopped scallions. Serve with a bowl of hot rice! Enjoy!