Better than any takeout you have ever ordered. The secret is beef bouillon in the sauce which gives it that deeply savory addictive quality you can never replicate at home. Flank steak, fresh garlic and ginger, oyster sauce, and a glossy sauce that coats every single piece beautifully. My family demolished it.
Place flank steak in freezer 20 minutes. Remove and slice into medium thin strips against the grain. Toss with soy sauce, cornstarch, sesame oil, and black pepper. Let sit 15 minutes.
Dissolve beef bouillon powder in 1/4 cup warm water. Whisk together with soy sauce, oyster sauce, honey, sesame oil, cornstarch, and beef broth until smooth. Set aside.
Blanch broccoli florets in boiling water for exactly 2 minutes. Drain and set aside.
Heat vegetable oil in a large wok over highest heat. Cook beef in a single layer in batches 2 to 3 minutes without touching until caramelized. Remove to a plate. Repeat with remaining beef.
Add butter to the same pan. Add minced garlic and grated ginger. Cook 60 seconds stirring constantly. Add sliced onion and cook 2 minutes.
Add blanched broccoli. Pour sauce over everything. Add beef back in. Toss until sauce thickens and coats everything glossy and beautifully. About 2 minutes.
Serve immediately over jasmine rice. Garnish with sesame seeds and sliced green onions. Sriracha on the side for heat lovers.
Notes
The beef bouillon is the secret ingredient. One teaspoon dissolved in warm water added to the sauce gives you that deeply savory addictive takeout quality that home cooking rarely achieves. Do not skip it.
Always slice flank steak against the grain. Look at the muscle fibers and cut perpendicular to them for tender beef every single time.
Partially freeze the steak for 20 minutes before slicing. Cleaner easier cuts every time.
Cook beef on the highest heat your stove will produce. High heat means sear not steam.
Cook beef in batches every single time. Crowding the pan ruins the caramelization.
Have your sauce ready before you start cooking. Stir fry moves fast.
Blanch the broccoli first. Two minutes in boiling water gives you perfectly tender bright green broccoli.
Store in the fridge up to 4 days. Gets even better overnight as the beef absorbs more flavor.
Reheat in a skillet with a splash of water or beef broth to loosen the sauce.