Season the chicken with salt and pepper. Set aside.
Using a 6-quart Instant Pot, press the “Sauté (High)” function and add the oil. When “Hot” appears on the screen, add four chicken skin side down and cook until brown, about 4 minutes. Gently flip the chicken over and brown the other side, about 2 minutes. Transfer the browned chicken onto a plate. Repeat the browning process with the rest of the chicken.
Press “Cancel” and then using oven mitts, carefully remove excess oil from the pot. Arrange the browned chicken skin side down at the bottom of the pot. Add the vinegar, soy sauce, garlic and bay leaves. Lock the lid and set the valve to sealing position. Press “Pressure Cooker (High)” and manually set the timer to 10 minutes.
When the time is done, carefully quick release the pressure and open the lid. Using a tong, carefully flip over the chicken pieces (skins side up). This step makes sure the chicken pieces are fully coated with the sauce.
Press “Sauté “and let the sauce boil for 10 to 12 minutes, depending on much sauce you desire. Stir in the sugar.
Remove the bay leaves. Serve with rice.