Preheat the oven to 400 degrees Fahrenheit.
Place the cornstarch and cold water in a small saucepan and stir together to combine.
Add in the sugar, soy sauce, cider vinegar, minced garlic, ginger, honey and pepper.
Stir together and heat, stirring slowly until the sauce comes to a boil. Turn off the heat.
Place the chunks of chicken in an oven-proof dish. Pour over the sauce and stir if needed to make sure all of the chicken is coated in the sauce.
Place in the oven (no lid needed) to cook for 30-35 minutes, stirring once or twice during cooking to ensure the top of the chicken doesn't get too dark. Check the chicken is cooked by cutting open a large piece and ensuring it's no longer pink in the middle (place back in the oven for another few minutes if it is).
Serve the chicken with boiled rice and green vegetables, topped with sesame seeds and chopped scallions.