Cook the noodles
Boil noodles according to package directions. Drain and set aside.
Mix the sauce
In a small bowl, whisk together soy sauce, oyster sauce, sugar, sesame oil, and water.
Cook the protein (optional)
Heat oil in a large wok or skillet. Cook protein until fully done. Remove and set aside.
Sauté vegetables
In the same pan, add garlic and ginger. Cook for 30 seconds. Add vegetables and stir-fry until crisp-tender.
Combine
Add noodles, protein, and sauce to the pan. Toss over high heat until well coated and heated through.
Serve
Garnish with green onions and serve immediately.