Ingredients:

  • 5 lbs Flank Steak (or Skirt Steak), sliced thinly against the grain
  • 2 tbsp Light Soy Sauce (low sodium), divided
  • 1 tsp Rice Vinegar
  • 2 tbsp Cornstarch (Cornflour), divided
  • 1/4 tsp Bicarbonate of Soda (Optional)
  • 1/2 tsp Sesame Oil
  • 3 tbsp Cooking Oil (Peanut or Vegetable), divided
  • 1 medium Yellow Onion, cut into large wedges
  • 2 large Green Bell Peppers, cut into 1-inch squares
  • 1 large Red Bell Pepper, cut into 1-inch squares
  • 1 tbsp Fresh Ginger, minced
  • 2 cloves Garlic, minced
  • 1 cup Beef Stock (low sodium)
  • 2 tbsp Oyster Sauce
  • 1 tsp Brown Sugar (or Honey)
  • 2 tsp Freshly Ground Black Pepper (coarse grind)
  • 2 tbsp cold water (for slurry)

Instructions:

  1. Slice the Steak: Slice the flank steak thinly, against the grain, into bite-sized strips. In a mixing bowl, combine the sliced beef with 1 tbsp light soy sauce, rice vinegar, 1 tbsp cornstarch, bicarbonate of soda (if using), and sesame oil. Toss well. Allow the beef to marinate at room temperature for at least 20 minutes (the velveting process).
  2. Prepare Aromatics and Sauce (Mise en Place): Cut all bell peppers and onion into uniform 1-inch pieces. Mince the garlic and ginger. In a separate bowl, whisk together the beef stock, oyster sauce, remaining 1 tbsp soy sauce, and brown sugar. Set aside. In a small cup, whisk the remaining 1 tbsp of cornstarch with 2 tbsp of cold water to form the slurry.
  3. Sear the Beef: Place the wok or skillet over high heat. Add 2 tbsp of cooking oil and heat until shimmering and almost smoking. Add the marinated beef strips, ensuring not to crowd the pan (cook in batches if necessary). Stir-fry quickly for 1–2 minutes until the outside is deeply browned. Immediately remove the beef and any accumulated juices from the pan and set aside.
  4. Sauté Vegetables and Aromatics: Add the remaining 1 tbsp of oil to the hot wok. Add the onion wedges and stir-fry for 1 minute. Add the green and red bell peppers and stir-fry for 2–3 minutes until crisp-tender. Clear a space in the center, add the minced garlic and ginger, and cook for 30 seconds until fragrant. Toss everything together.
  5. Build and Thicken the Sauce: Pour the prepared sauce mixture over the vegetables and bring the liquid to a rolling boil. Stir in the generous two teaspoons of freshly ground black pepper. Reduce the heat slightly. Re-whisk the cornstarch slurry and pour it into the boiling sauce while stirring constantly. The sauce should immediately thicken and become glossy. Cook for 30–60 seconds.
  6. Finish and Serve: Return the seared beef (and any resting juices) to the pan. Toss everything gently for 30 seconds to coat the beef and vegetables completely in the glossy sauce. Taste and adjust seasoning. Serve immediately while hot, ideally over steamed jasmine rice.