To make the sauce. Combine all ingredients in a glass jar. Add 1/3 cup water.Cook the noodles for 2-3 minutes, until just soft. Drain and set aside. In a large skillet, combine the chicken, garlic powder, ginger, black pepper, and cornstarch. Toss with tamari. Cook over medium-high heat until browned, about 8 minutes. Add the cashews. Cook for 2 minutes, until the cashews are golden. Pour over the sauce. Cook until the sauce thickens slightly. Then, add the noodles. Toss well to coat and remove from the heat. Serve the noodles and chicken with sesame seeds and green onions.