Begin by slicing your beef flank steak against the grain into thin strips. In a mixing bowl, combine the beef with baking soda, light soy sauce, peanut oil, and cornstarch. Let it marinate for 15 minutes.

In a separate bowl, whisk together chicken broth, oyster sauce, dark soy sauce, sugar, and a bit of cornstarch until smooth. Set it aside.

Heat a large skillet over medium-high heat. Add a splash of peanut oil and once shimmering, add the marinated beef in a single layer. Sear for 1-2 minutes until golden brown and slightly crispy, then set it aside on a plate.

In the same skillet, add more peanut oil if needed and toss in sliced white onion, minced garlic, and grated ginger. Stir-fry for about 2 minutes until the onions are translucent.

Add your asparagus (or chosen vegetables) to the skillet and stir-fry for about 1 minute until just tender but crisp.

Return the seared beef to the skillet, pour in the prepared sauce, and toss everything together. Cook for another 1-2 minutes until the sauce thickens.

Remove from heat and plate the stir-fry. Serve hot alongside steamed rice or noodles.