Begin by slicing your beef flank or skirt steak into thin strips for quick cooking. In a bowl, combine the beef with baking soda, light soy sauce, peanut oil, and cornstarch. Mix everything well and let it marinate for about 20 minutes at room temperature.

While the beef is marinating, prepare the sauce for your beef with oyster sauce. In a small bowl, whisk together the chicken broth, oyster sauce, light soy sauce, dark soy sauce, sugar, and cornstarch.

Heat a large skillet over medium-high heat and add 1 tablespoon of peanut oil. Once the oil is shimmering, carefully add the marinated beef in a single layer.

In the same skillet, add another tablespoon of oil if needed, then toss in the white onion, minced garlic, and grated ginger. Sauté these aromatics for about 2 minutes until they become fragrant.

Next, add the asparagus to the skillet, stirring frequently, and cook for about 1 minute.

Give the sauce mixture a quick stir to redistribute the cornstarch, then pour it into the skillet with the sautéed vegetables.

Now, return the seared beef to the skillet, stirring to coat it well with the thickened sauce and vegetables.

Remove the skillet from heat and serve your delicious beef with oyster sauce immediately over white rice.