In a small bowl, whisk together soy sauce, water, honey, rice vinegar, garlic, and ginger to create the teriyaki sauce.
Heat vegetable oil in a large skillet over medium-high heat. Add chicken pieces and cook until browned and cooked through, about ten minutes.
Pour the teriyaki sauce over the cooked chicken and bring to a simmer.
In a separate bowl, mix cornstarch with cold water to make a slurry. Stir into the skillet to thicken the sauce.
Garnish the Teriyaki Chicken with green onions and sesame seeds before serving.