Begin by preparing all your ingredients. Cut broccoli into small florets, mince the garlic and ginger, and have the sauces ready.
In a large skillet or wok, heat the vegetable oil over medium-high heat.
Add the ground beef and cook until browned, breaking it apart with a spatula, about 5-7 minutes. Drain excess fat if necessary.
Stir in the minced garlic and ginger and cook for about 1 minute until fragrant.
Add the broccoli florets to the skillet and stir-fry for about 3-4 minutes, until they are tender but still crisp.
In a small bowl, mix together the soy sauce, oyster sauce, sesame oil, cornstarch, and water. Pour this sauce over the beef and broccoli mixture.
Toss everything together and cook for an additional 2-3 minutes, until the sauce thickens and coats the beef and broccoli nicely. Season with salt and pepper to taste.
Serve hot over cooked rice or noodles.