Bring a large pot of lightly salted water to boil.
Add in broccoli florets and cook for about 2 minutes, until just softened.
Drain broccoli and set aside. This step can be done hours ahead of time while the meat is marinating.
Mix cornstarch and water.
Place beef in a small bowl and pour cornstarch mixture, making sure all the meat is submerged.
Add in soy sauce and bean sauce. Mix to combine into a marinade. Let beef marinate in the fridge for at least 30 minutes.
When ready to stir fry, heat oil in a wok or deep frying pan. Add ginger and garlic and cook until just turning brown.
Add parboiled broccoli florets and stir fry.
Remove broccoli florets and set aside.
Add beef plus marinade into the hot wok. As the beef cooks, the marinade should begin to reduce into a thick sauce. If your beef is cooking too slowly and the sauce begins to stick to the wok, simply add a little bit more water.
When beef is almost fully cooked and the sauce has thickened to your desired consistency, add the broccoli back in.
Mix to combine and add salt to taste.