Marinate the Beef: In a medium bowl, combine beef, 2 tablespoons soy sauce, and cornstarch. Mix well and let sit for 15 minutes.
Heat the Pan: Warm vegetable oil in a large pan or wok over medium-high heat.
Aromatics: Add garlic and ginger, stir-frying for 30 seconds until fragrant.
Cook Onions: Toss in the sliced onion and cook until soft and translucent, about 2-3 minutes.
Add Beef: Stir in the marinated beef and cook until browned on all sides, just a few minutes.
Add Sauce: Pour in oyster sauce, remaining soy sauce, sugar, and beef broth. Stir to coat beef and onions evenly.
Simmer: Let simmer for a few minutes until the sauce thickens.
Serve: Plate hot over rice or noodles. Enjoy immediately.
Serving and Storage Tips
