12 ounces skinless, boneless chicken breast, cut into 1-inch cubes
2 garlic cloves, thinly sliced
4 teaspoons soy sauce
1 teaspoon Shao Hsing rice wine or dry sherry
3 teaspoons cornstarch
1/2 teaspoon plus 1 tablespoon sugar
1/2 teaspoon salt
1/8 teaspoon ground white pepper
1/3 cup chicken broth
2 teaspoons black soy sauce
2 teaspoons sesame oil
2 tablespoons rice vinegar
2 tablespoons ketchup
1 tablespoon plus 2 teaspoons vegetable oil
1 green bell pepper, cut into 1-inch cubes
1 red bell pepper, cut into 1-inch cubes
3 scallions, cut into 2-inch pieces

1. In a medium bowl combine the chicken, garlic, 2 teaspoons of the soy sauce, the rice wine, 1 1/2 teaspoons of the cornstarch, the 1/2 teaspoon sugar, 1/4 teaspoon salt, and the pepper. Set aside. In a small bowl combine the broth, black soy sauce, sesame oil, rice vinegar, ketchup, and the remaining 1 tablespoon sugar, 2 teaspoons soy sauce, 1 1/2 teaspoons cornstarch, and 1/4 teaspoon salt. Set the sauce aside.
2. Heat a 14-inch flat-bottomed wok over high heat until a bead of water vaporizes within 1 to 2 seconds of contact. Swirl in the 1 tablespoon vegetable oil and carefully add the chicken, spreading it evenly in the wok. Cook undisturbed 1 minute, letting the chicken begin to brown. Then, using a metal spatula, stir-fry 1 minute or until the chicken is browned on all sides but not cooked though. Transfer to a plate.
3. Swirl the remaining 2 teaspoons vegetable oil into the wok, add the peppers and scallions and stir-fry 30 seconds. Stir the sauce and swirl it into the wok. Return the chicken to the wok and stir-fry 1 to 2 minutes or until the chicken is just cooked through and the sauce has slightly thickened. Serves 4 as part of a multicourse meal.