Preparation

• In a medium bowl, combine the broth, soy sauce, rice wine, sugar, and pepper flakes. Set aside. Trim 1/4 inch from the base of each head of bok choy. Separate the bok choy base into individual stalks. Place the bok choy in a salad spinner. Fill the spinner with cold water, and swish to remove any grit or dirt. Do this several times, and finally whirl them dry in a salad spinner.
• In a shallow bowl, combine 1 Tbs. of the cornstarch and the salt. Dust both sides of the chicken with the cornstarch mixture.
• Heat a 14-inch flat-bottomed wok (preferably seasoned carbon steel) or a 12-inch stainless-steel skillet over high heat until a bead of water vaporizes within 1 to 2 seconds of contact. Add the oil, swirl to coat the pan, add the chicken skin side down, distributing it evenly in the wok. Reduce the heat to medium and cook, undisturbed, until golden-brown, 3 to 4 minutes.
• Using a metal spatula, turn the chicken over, and add the garlic and ginger. Cook until the chicken is golden-brown but not cooked through, 3 to 4 minutes. Increase the heat to high, stir the broth mixture, and swirl it into the wok. Cover, reduce the heat to low, and simmer for 5 minutes. Turn the chicken over and simmer until just cooked through, about 5 minutes more.
• Transfer the chicken to a platter. Increase the heat to high, add the bok choy to the wok, cover, and cook 1 minute. Uncover, and cook, stirring occasionally, until crisp-tender, 1 to 2 minutes. Turn off the heat. Arrange the bok choy around the chicken. Combine the remaining 1 tsp. cornstarch and 2 tsp. cold water. return the pan to high heat, and bring the liquid to a boil. Add the cornstarch mixture, and cook, stirring constantly, until just thickened, 30 seconds to 1 minute. Pour the sauce over the chicken and bok choy, and serve.