1In a medium bowl combine the chicken, 1 tablespoon of the oil, 1 teaspoon of the cornstarch, ½ teaspoon of the salt, and pepper. Stir to combine. In a small bowl combine the remaining ½ teaspoon cornstarch and 1/3 cup cold water. In another small bowl combine the paprika and cumin.
2Heat 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 remaining 1 tablespoon oil, add the onions, then, using a metal spatula, stir-fry 30 seconds or until the onions begin to wilt. Push the onions to the sides of the wok, carefully add the chicken, and spread it evenly in one layer in the wok. Cook undisturbed for 1 minute, letting the chicken begin to sear. Stir-fry 30 seconds or until the chicken is almost completely opaque. Add the ginger, garlic, and the paprika mixture, and stir-fry 1 minute or until the aromatics are fragrant and the chicken is well coated in the spices.
3Add the red and green bell peppers, reduce the heat to medium, and stir-fry 2 minutes or until the peppers begin to soften. (Do not be alarmed if the spices stick a little to the bottom of the wok.) Add the fish sauce, chilies, zucchini, and the remaining ¼ teaspoon salt, and stir-fry 1 minute or until almost all the liquid has evaporated. Restir the cornstarch mixture, swirl it into the wok, increase the heat to high, and stir-fry 1 minute or until the chicken is just done and the vegetables are crisp-tender. Remove the wok from the heat and stir in the chili powder.