Combine chicken, 1 tablespoon soy sauce and 1-1/2 teaspoons cornstarch in medium bowl; toss to coat. Let stand 30 minutes at room temperature.
In a small bowl, whisk together 2 tablespoons soy sauce, 1-1/2 teaspoons cornstarch, 3 tablespoons water, vinegar, sesame oil and sugar.
Heat peanut oil in wok or large non-stick skillet over hight heat until very hot. Add chicken mixture and stir-fry 2 minutes. Using slotted spoon, transfer chicken to medium bowl. Add green onions, chili sauce, garlic and ginger to wok or skillet and cook 2 minutes. Add chicken and soy sauce mixture; cook until chicken is cooked through, about 2 minutes.