For the sauce: In a small bowl, whisk together soy sauce, oyster sauce, rice vinegar, brown sugar, and fish sauce. Set aside.
For the stir fry: Fill a large bowl with room temperature water and submerge the noodles. Set them aside while you prepare the rest of the stir fry.
Place chicken pieces in a small bowl and sprinkle with flour and cornstarch. Toss to combine.
Heat a large skillet or wok over medium-high heat. Add the olive oil. When oil is hot, carefully shake off any excess flour from the chicken and then add the chicken pieces to the hot oil. Sear for 2 minutes and then flip the chicken.
Add the carrot and onion and cook for an additional 5 minutes, or until the vegetables are tender and the chicken is almost cooked through.
Next add the cabbage and snow peas and cook for an additional minute.
Move the chicken and vegetables to one side of the pan and add the beaten egg to the opposite side. Stir the egg for 1-2 minutes or until it is scrambled and fully set. Mix into the vegetables and chicken.
Drain the noodles well and add them to the pan. Next add the prepared sauce - use as little or as much as you like, although I do recommend using at least half of it. Stir until the sauce coats the noodles and chicken. Cook for an additional 1-2 minutes or until the glass noodles turn clear instead of white.
Remove pan from the heat and serve immediately. Garnish individual servings with green onion, cilantro, and/or sesame seeds. If you'd like to add a bit of heat, drizzle with sriracha or chili oil, or add a sprinkle of dried red chili flakes.
