Prep like a pro: Thinly slice the beef against the grain. Cut broccoli into small bite-size florets. Mince the garlic, grate the ginger, and slice the green onions. Measure everything—stir fries go fast.

Mix the sauce: In a bowl, whisk soy sauce, oyster sauce, dark soy (if using), brown sugar, rice vinegar, chili sauce, broth, and cornstarch until smooth. Set aside.

Cook the noodles: Boil according to package directions until just shy of done. Drain and rinse briefly with cool water to stop cooking. Toss with a little oil to prevent sticking.

Sear the beef: Heat 1 tablespoon oil in a large skillet or wok over high heat until shimmering. Add beef in a single layer. Cook 1–2 minutes per side until browned but still tender. Work in batches if needed. Transfer to a plate.

Stir-fry the broccoli: Add the remaining oil to the pan. Toss in broccoli and the white parts of the green onions. Stir-fry 2–3 minutes. Splash in 2–3 tablespoons water, cover for 1 minute to steam until crisp-tender. Uncover.

Add aromatics: Push broccoli to the edges. Add garlic and ginger to the center. Stir 30 seconds until fragrant.

Sauce it up: Return beef and any juices to the pan. Pour in the sauce and stir constantly. It will thicken and turn glossy in about 1 minute.

Toss with noodles: Add noodles and the green parts of the onions. Toss until everything is coated and heated through. Drizzle with sesame oil, taste, and adjust seasoning—more soy for salt, more vinegar for brightness, or a bit of sugar if you like it sweeter.

Finish and serve: Sprinkle with sesame seeds or chili oil if you like. Serve hot.