In a bowl, marinate the sliced beef with soy sauce, shaoxing wine, cornstarch, and oil. Let sit for 15 minutes.
While the beef marinates, slice the ginger and onion. Separate scallions into white and green parts. Rinse the bean sprouts.
In a small bowl, mix all the sauce ingredients and set aside.
Heat a pan or wok over high heat. Add oil and sear the beef for about 2 minutes until browned. Remove and set aside.
Re-oil the pan and sauté the ginger for 1 minute.
Add onions and white scallion parts. Stir-fry for 3 minutes until slightly softened.
Add the fresh rice noodles, marinated beef, and sauce. Toss everything together until the noodles are well coated.
Add in the scallion greens and bean sprouts, toss again, and cook for 1–2 more minutes.
Serve hot in a bowl. Garnish with extra scallions if desired.
