Slice beef thinly against the grain
Mix beef with soy sauce, cornstarch, and a little oil
Marinate for 15 to 20 minutes
Cut broccoli into florets
Blanch broccoli in boiling water for 1 to 2 minutes
Drain broccoli and set aside
Heat oil in a skillet or wok over high heat
Stir-fry beef until browned
Remove beef from the pan
Add garlic and ginger to the pan
Add broccoli and stir-fry briefly
Mix soy sauce, oyster sauce, beef broth, sugar, and cornstarch
Pour sauce into the pan
Return beef to the pan
Toss until everything is coated and the sauce thickens
Serve hot over rice