There are two ways to prepare the sauce: In a small bowl, add the soy sauce, white vinegar, water and add brown sugar to a small-size bowl and season according to your liking. Add more soy sauce, white vinegar, or sugar, or cut some. Adjust accordingly. Set aside. Or, you can add the sauce ingredients as you go along.
Place the inner pot and push the saute mode button. Saute function start, and it will add heat to the oil. Add oil and saute the onion and garlic. Sear and brown the pork cut on all sides.
Pour the Adobo sauce into the pot and add the ground pepper, pepper corns, and bay leaves and cover using the pressure cooker lid. Push the pressure cooker button. Set the temperature on high and cooking time to twenty-five minutes. The instant pot will build its pressure. When ready, the floating valve will release, and it will start pressure c-now the cooking time, which is twenty-five minutes.
After twenty-five minutes, the floating valve goes down, and you can now push the steam release button.