Prepare Vegetables: Start by cutting the green onions, celery, and white onion.
Combine Sauce Ingredients: Combine oyster sauce, light soy sauce, dark soy sauce, chicken bouillon powder, sugar, and water in a bowl.
Boil Noodles: Boil the noodles until they loosen up, then drain and let them dry.
Stir Fry Vegetables: Stir fry the white onions, white parts of the green onions, and bean sprouts on high heat until the bean sprouts have softened slightly, then take them out.
Cook Noodles: Add more oil to the wok, spread out the parboiled noodles, and cook on medium heat for about five minutes, stirring and flipping occasionally.
Combine and Serve: Stir in the sauce until well incorporated, then add the stir-fried vegetables and remaining green onions. Add sesame oil and more fresh bean sprouts, cook for a final 30 seconds, and plate.