01 - In a bowl, combine sliced chicken with soy sauce, cornstarch, and sesame oil. Set aside for at least 10 minutes.
02 - In a small bowl, whisk together soy sauce, oyster sauce, hoisin sauce, sugar, white pepper, and water. Set aside.
03 - Prepare noodles according to package instructions. Drain and rinse under cold water. Toss lightly with 1 tsp oil to prevent sticking.
04 - Heat 1 tbsp oil in a large wok or skillet over high heat. Add chicken and stir-fry until just cooked through, about 3-4 minutes. Remove and set aside.
05 - Add remaining 1 tbsp oil to the wok. Add garlic and onion; stir-fry for 1 minute. Add carrot, bell pepper, and snow peas; stir-fry for 2-3 minutes until just tender.
06 - Return chicken to the wok. Add cooked noodles, bean sprouts, and spring onions. Pour in the sauce and toss everything together over high heat for 2-3 minutes until well combined and heated through. Serve immediately.