Preheat your oven to 425F.
In a small saucepan, combine together 1 Tablespoon of cornstarch, 1 Tablespoon cold water, 1/2 cup soy sauce, 1/2 cup sugar, 1/4 cup apple cider vinegar, 1-2 minced garlic cloves, 1 Teaspoon of ground ginger, and 1/2 teaspoon black pepper.
Whisk until all of the ingredients are well blended. Cook on low heat, stirring often, until the sauce bubbles and thickens.
Remove from heat and set aside.
Wash and dry the chicken breasts. If they are large, cut in half.
Place pieces of chicken between plastic wrap and flatten each piece by using a flat side of a meat tenderizer.
Place the chicken breasts on a greased baking dish. Brush chicken with the sauce, then turn over and brush the other side.
Bake at 425F for 15-20 minutes, and then take the dish out, flip the chicken over and bake for another 15-20 minutes. Brush with sauce every 5-10 minutes while baking. This will create a beautiful glaze on the top of the chicken.
Before serving, slice each chicken breast and sprinkle with toasted sesame seeds.
Enjoy this simple Teriyaki Chicken dish with white rice and steamed vegetables of your choice!