Slice the flank steak as thinly as possible and marinate it in soy sauce and cornstarch for about 10 minutes.

While the steak is marinating, bring a pan of water to boil and blanch the broccoli for about 2 minutes until bright and slightly tender. Drain and set aside.

Heat a large skillet or wok over medium-high heat, add a tablespoon of vegetable oil, and swirl around the pan.

Add the marinated beef and sear for about 2-3 minutes without stirring. Flip and cook for another 2-3 minutes until just cooked through, then remove from the pan.

In the same skillet, add another tablespoon of oil and sauté the minced garlic and grated ginger for about 30 seconds until fragrant.

Add the blanched broccoli and beef back into the skillet.

Pour in the beef broth, soy sauce, oyster sauce, and brown sugar. Stir and let simmer for a couple of minutes until the sauce thickens, adjusting flavor with salt and pepper if needed.

Garnish with sesame seeds or chopped scallions and serve over white rice, quinoa, or glass noodles.