Instructions:
- Combine sliced beef with marinade ingredients (Soy, Wine, Baking Soda, Cornstarch, 1 Tbsp Oil). Mix well until coated. Marinate for 15 minutes minimum.
- Prepare the Umami Sauce by whisking all sauce ingredients (Beef Broth, Light Soy Sauce, Dark Soy Sauce, Oyster Sauce, Sugar, Black Beans) together in a small bowl. Set aside. Chop vegetables and prepare the cornstarch slurry separately.
- Heat 1 Tbsp oil in the wok over high heat until shimmering. Quickly sear the beef in batches (do not overcrowd the pan!) until just browned on the outside but still slightly pink inside (about 60–90 seconds per batch). Remove beef and set aside immediately.
- Add the remaining 2 Tbsp of oil to the wok. Reduce heat slightly to medium-high. Add onions and peppers. Stir-fry rapidly for 2–3 minutes until they start to soften but retain a good bite (al dente).
- Push vegetables to the side. Add minced garlic, grated ginger, and rinsed black beans to the clear space. Cook for 30 seconds until fragrant—be careful not to burn the garlic!
- Pour the prepared Umami Sauce mixture over the vegetables. Bring to a simmer, scraping up any browned bits from the bottom of the pan.
- Whisk the cornstarch slurry one more time and pour it slowly into the simmering sauce, stirring constantly until the sauce thickens and turns glossy.
- Return the seared beef to the wok. Toss quickly and gently to coat the beef and vegetables thoroughly in the glossy sauce. Cook just until the beef is heated through (about 30 seconds).
- Taste and adjust seasoning if necessary. Serve immediately, ideally over steamed rice.