Heat 1 teaspoon of oil in a large pan over medium heat. Add broccoli and cook for about 4 minutes until tender.
Add ginger and garlic, cook for 30 seconds until fragrant. Remove and set aside.
Wipe the pan clean and heat remaining oil over high heat.
Season beef with salt and pepper, then cook in batches for 3–4 minutes per side until browned.
Return broccoli to the pan and cook for 2 minutes.
In a bowl, whisk oyster sauce, beef broth, sugar, sesame oil, and soy sauce.
Mix cornstarch with 1 tablespoon cold water.
Pour sauce into the pan, cook for 30 seconds. Add cornstarch slurry and bring to a boil.
Cook for 1 minute until thickened.
Serve your beef and broccoli stir fry immediately with rice if desired.