Combine the first 4 ingredients in a small bowl to make the Seasoning Mix. Sprinkle all surfaces of the chicken evenly with 2 teaspoons of the mix and rub it in well.
Dissolve the cornstarch in 4 tablespoons of the stock and set aside. Preheat a heavy 12‑inch skillet, preferably nonstick, over high heat to 350°, about 5 minutes.
Add the chicken, stir, and cook until it starts to brown, about 2 minutes. Add the fresh ginger and onions, stir and cook for 2 minutes. Add the remaining vegetables, Magic Pepper Sauce® and seasoning mix, stir, and cook for 3 minutes. Stir in the tamari and vinegar, stirring occasionally, until much of the liquid evaporates and the sauce becomes thick and syrupy. Stir in the tomato sauce and remaining stock, bring to a boil, and cook for 2 minutes. Add the cornstarch mixture, cook for 2 minutes, remove from the heat, and, if desired, add the artificial sweetener. Serve over the rice.
Note: Tamari is a very flavorful kind of soy sauce, available in specialty markets and the international or ethnic food sections of many supermarkets. If it is unavailable where you shop, use the best soy sauce you can find.
Note: This recipe is a no-added fat, no processed sugar recipe from Chef Paul Prudhomme's Fork In The Road cookbook.
* If you prefer a little spicier dish, simply add more Magic Pepper Sauce®.