Toss the chicken pieces with the soy sauce in a large bowl. Refrigerate for at least an hour, but up to overnight.
Remove the chicken from the soy sauce and let the excess drip back into the bowl.
Set the Ninja Foodi to the high sear/sauté function.
Add the chicken pieces to the inner pot, skin side down. Sear on high sear/sauté until the skin is golden brown on all sides. You will have to do this in batches. You don't want to over crowd the pan. Once the chicken has browned set it aside.
While the chicken is browning, whisk 1 ½ cups coconut milk, ½ cup cider vinegar, 2 tablespoon brown sugar, and peppercorns into the soy sauce.
Use a sharp knife to separate the white parts of the scallions from the green. Slice the white part in half long ways and thinly slice the green parts for garnish.
Pour the soy sauce-coconut milk mixture into the inner pot. Add the white parts of the scallions and the 3 bay leaves. Nestle the chicken pieces into the sauce.
Put the pressure lid on. Turn the valve to seal and set the pressure on high for 10 minutes. Natural release for 5 minutes and then manually release the remaining pressure.
Carefully transfer the chicken pieces to a platter and cover with foil to keep warm while you are finishing the sauce.
Fish out the bay leaves. Set the Ninja Foodi to the high sear/sauté function. Bring the sauce to a boil and cook until it has reduced and thickened as much as you would like.
Taste and adjust seasoning. If you feel like the flavor is too intense, you can add a few tablespoon of water or a bit more sugar to mellow it out.
Pour the sauce over the chicken and garnish with the sliced green parts of the scallions. Serve with rice to soak up all of the amazing flavors from the sauce.