Preheat the oven to 190°C (375°F).
In a glass 9"x10" baking dish, whisk together all ingredients except for the chicken until combined.
Add the chicken to the dish and spoon some of the mixture over each piece. Marinate the chicken in the mixture ahead of time if you like.
Place the baking dish in the oven uncovered and bake for 45-60 minutes. Spoon some of the sauce over the chicken a few times as it cooks.
Once the chicken is finished cooking, remove each piece from the baking dish and place them on a serving plate.
Skim the fat off the top of the drippings as much as possible. If there's a little fat left, that's okay too.
Combine about 1/4 of the drippings and the cornstarch in a small dish and set aside. Mix it together using a whisk to make sure there are no lumps.
Pour the remaining drippings into a saucepot and bring to a boil.
Add the cornstarch mixture and lower the heat. Stir constantly using a whisk until the sauce reaches the desired consistency.
Remove from the heat and serve with the chicken.