Prepare chicken: Whisk together the Chicken Marinade ingredients in a medium bowl (soy sauce, sesame oil, cornstarch, pepper). Add chopped chicken and toss to evenly coat; set aside.
Prepare the glass noodles: Soak the noodles in a bowl of hot water until tender, stirring occasionally so they don’t stick together, about 8-10 minutes. Drain and rinse the noodles in cold water. Toss with 1 teaspoon toasted sesame oil. Set aside. Make the sauce: Meanwhile, whisk the sauce ingredients together and prep the veggies, set aside.
Stir fry the chicken: Heat 1 tablespoon oil in a wok over high heat or a nonstick skillet over medium-high heat. Add chicken and stir fry until cooked through, about 4-5 minutes; remove to palate. Stir fry the veggies: Heat another tablespoon of oil in the skillet. Add onions and stir fry for 3 minutes, until starting to caramelize. Add cabbage, carrots and bell pepper and stir-fry for about 1 minute. Add the tomatoes, ginger and garlic, and stir fry for 1 minute, until vegetables are almost to desired crisp-tenderness (they will cook a little more with the noodles). Cook the eggs: Push the vegetables to the perimeter of the pan. Add a drizzle of oil to the center of the pan. Add the beaten eggs to the hot oil and scramble in the center until cooked.
Stir fry everything together: Add chicken back to the skillet, along with the noodles and sauce and toss to combine. Stir fry everything together until evenly coated in the sauce. Adjust to taste (I like additional white pepper).
Serve: Garnish with green onions, chilies, and sesame seeds if desired.