Mix Sauce: To a wide-mouth mason jar, add the chicken broth, soy sauce, oyster sauce, cornstarch, sesame oil, and maple syrup. Cover and shake until the cornstarch is dissolved. Set aside.
Soak Noodles: Add the rice noodles to hot water and soak for 15 minutes, or follow instructions on the package of noodles if not using angel hair rice noodles.
Cook Veggies: To a large skillet or wok, heat the avocado oil over medium-high heat. Add the chopped coleslaw mix. Stir fry until tender, 4-5 minutes. Next, add the chopped bean sprouts and chopped mushrooms, and stir fry for 1-2 minutes. Remove to a plate.
Cook Noodles: Drain the rice noodles. To the same skillet, add another tablespoon of avocado oil, and stir fry the noodles for 1 minute. Add the sauce. Stir. Then add the cooked veggies. Stir until combined. Top with chopped green onions and serve immediately.