In a bowl, toss the chicken with the sugar, red pepper flakes, and Szechwan pepper. Let sit.
To make the rice noodles, place 1/4 pound of rice stick noodles in a bowl, cover with boiling water and let stand until softened. Drain, cover, and set aside until ready to serve.
To make the seasoning blend, in a blender or small food processor, combine the sesame oil, garlic cloves, ginger, and 2 tablespoons of the green onions, and puree on high speed.
To make the cooking sauce, in a small bowl, combine the chicken stock, soy and hoisin sauces. In another small bowl, dissolve the cornstarch in the sherry. Set aside.
Heat 2 tablespoons of the peanut oil to smoking in a wok or very large skillet over high heat. Add the pureed seasoning blend and cook for 15 seconds. Add chicken and stir-fry until mostly opaque, but not cooked through all the way, about 2 minutes. Remove to a plate. Add the remaining tablespoon of oil, then the onions, carrots, bell pepper, zucchini, and celery, and cook, stir-frying for 30 seconds. Add the bok choy and mushrooms and cook for 1 minute. Add the reserved cooking sauce and return the chicken to the wok. Stir and toss until the sauce glazes the food and the chicken is cooked through, about 2 minutes. Remove from the heat and whisk in the cornstarch mixture. Return to the heat and return to a boil. Cook, stirring, until thickened, about 1 minute.
Remove from the heat and stir in the remaining 2 tablespoons of green onions, the cashews, bean sprouts, and cilantro. Adjust seasoning to taste, with additional soy sauce, if desired.
Serve immediately over blanched rice noodles.
Yield: 4 to 6 servings