Toss the shaved beef with all the marinade ingredients until evenly coated.
Let it sit for 15–20 minutes.
Blanch broccoli in boiling water for 30–60 seconds (1–2 minutes if frozen).
Rinse with cold water and drain to stop cooking.
Combine all sauce ingredients in a small bowl and mix until smooth.
Heat a pan or wok over medium-high heat with a bit of oil.
Add beef in a single layer and cook until browned.
Remove beef and set aside.
In the same pan, add a little more oil if needed.
Add garlic and ginger, stir-fry until fragrant (about 30 seconds).
Pour in the sauce and bring to a simmer.
Add the broccoli and beef back into the pan.
Toss everything together until the sauce thickens and coats the ingredients evenly.
Serve hot over steamed white rice.