Slice the beef into thin strips and season lightly with salt and black pepper.
Heat oil in a wok or large skillet over high heat.
Add the beef and stir-fry until browned and cooked through. Remove and set aside.
Add broccoli to the same pan and stir-fry until bright green and slightly tender.
Add minced garlic and ginger and cook for about 30 seconds.
Return the beef to the pan, add soy sauce and a little sesame oil, and toss everything together.
Cook for another 1–2 minutes, then serve hot with steamed rice or noodles.