In Medium Bowl, Combine 1 Tablespoon Vegetable Oil, Soy Sauce, Garlic, Ginger Root And Cornstarch. Toss Chicken In Sauce To Coat And Marinate 30 Minutes. In A Wok, Heat Remaining 2 Tablespoons Oil And Cook Peppers And Celery Over High Heat, Stirring Frequently Until Softened. Add Green Onions And Cook 2 Minutes More. Remove Vegetables From Wok. Drain Chicken And Pat Dry With Paper Towels. Add Chicken To Wok And Stir Fry Until Chicken Is Done, About 3 Minutes. Mix Remaining Ingredients Together In A Small Bowl. Add To Chicken With Vegetables; Simmer 3 Minutes.