Using the SAUTE feature set on NORMAL, heat about 1 tablespoon of oil. Add the onions and garlic and cook until softened.
Cancel the SAUTE function. Add the chicken, soy sauce, vinegar, bay leaves, red chili flakes, brown sugar, and salt and pepper to taste.
Close the lid making sure the valve is in SEALING position and cook on HIGH pressure for 14 minutes. Do a natural release for 10 minutes and manually release the rest of the pressure. Carefully open the lid.
Remove the chicken and arrange in a single layer, skin side up, on a grill pan. Broil for about 2 to 4 minutes or until crispy and lightly browned. Watch closely as it can burn easily.
Meanwhile, turn on the SAUTE function and cook the sauce for about 10 to 15 minutes or until reduced and thickened to desired consistency.
Season with salt and pepper to taste, if needed.
Place the chicken over steamed rice and spoon sauce on top. Serve hot.