🍽️ How to Make Mongolian Beef

🧆 Ingredients

• 300g beef flank (sliced thin)
• 1 onion (sliced)
• 1 green bell pepper (sliced)
• 2 tablespoons soy sauce
• 1 tablespoon oyster sauce
• 1 tablespoon hoisin sauce
• 1 tablespoon sugar
• 1 tablespoon cornstarch
• 1 tablespoon cooking oil
• 2 cloves garlic (minced)
• 1 thumb ginger (minced)
• 100ml water
• Salt to taste
• Green onions for garnish

🍳 Steps

1. Ingredient Preparation and Cleaning: Begin by thoroughly washing all fresh ingredients. Rinse the beef flank under cold running water and pat dry with paper towels. Inspect the beef for any sinew, connective tissue, or excess fat and trim as needed. Slice the beef thinly against the grain to maximize tenderness—this is crucial for a soft texture. When slicing, ensure each piece is uniform in thickness (about 1/8 inch) to promote even cooking. Wash the onion and green bell pepper under running water, then slice them into uniform strips for even cooking. Peel and mince the garlic and ginger, ensuring no skin or fibrous parts remain. Measure out the soy sauce, oyster sauce, hoisin sauce, sugar, cornstarch, and water. Preparing all ingredients in advance ensures a smooth workflow and prevents overcooking during stir-frying.

   Tip: If possible, freeze the beef for 20 minutes before slicing. This firms up the meat and makes it easier to cut thin, even slices.

2. Marinate the Beef: In a mixing bowl, combine the sliced beef with soy sauce, oyster sauce, hoisin sauce, sugar, and cornstarch. Mix thoroughly to coat each piece evenly. Allow the beef to marinate for at least 10–15 minutes. This step infuses the meat with flavor and helps tenderize it. The cornstarch forms a protective layer, keeping the beef juicy during high-heat cooking. For best results, marinate in the refrigerator if you have extra time. If marinating longer than 30 minutes, cover the bowl to prevent drying out.

   Tip: Add a teaspoon of Shaoxing wine or dry sherry to the marinade for extra aroma and tenderness.

3. Check Beef Maturity and Quality: Before cooking, check the beef slices for color and texture. Fresh beef should be bright red and slightly moist, not sticky or gray. If the beef has been marinated for longer, ensure it is still tender and not overly dry. Properly sliced and marinated beef will yield the best results in the final dish. If you notice any off smells or discoloration, discard the beef.

   Tip: For best texture, use beef that is well-marbled but not overly fatty.

4. Prepare the Aromatics: Heat a wok or large skillet over medium-high heat. Add the cooking oil and swirl to coat the surface. Once the oil is shimmering, add the minced garlic, ginger, and sliced onion. Stir-fry for 2–3 minutes until fragrant and the onion becomes translucent. Stir constantly to prevent burning the aromatics, as this base is essential for building depth of flavor. If using dried chilies for heat, add them at this stage.

   Tip: Use a carbon steel wok for best results, as it retains high heat and imparts a smoky flavor (wok hei).

5. Stir-Fry the Beef: Increase the heat to high. Add the marinated beef to the wok, spreading it out in a single layer for even searing. Allow it to sear undisturbed for about 30 seconds to develop a slight crust, then stir-fry briskly. Cook until the beef is just browned and no longer pink, about 1–2 minutes. Avoid overcooking, as thin beef slices can become tough quickly. If cooking in batches, do not overcrowd the pan—this ensures the beef sears rather than steams.

   Tip: Remove the beef from the wok as soon as it is no longer pink to keep it tender and juicy.

6. Add Vegetables and Sauce: Add the sliced green bell pepper to the wok. Pour in the measured water to help create a sauce and deglaze the pan, scraping up any flavorful bits stuck to the bottom. Stir-fry for another 2 minutes, allowing the bell pepper to soften but remain crisp. The sauce should thicken and coat the beef and vegetables evenly. If you prefer a thicker sauce, mix a little extra cornstarch with water and add as needed. Taste and adjust seasoning as desired.

   Tip: For extra color and nutrition, add a handful of snap peas or carrots sliced on the bias.

7. Check for Doneness and Adjust Seasoning: Properly cooked Mongolian Beef should have tender beef slices with a glossy, slightly sticky sauce. The bell pepper should be vibrant and slightly crisp, not mushy. Taste the dish and adjust salt or sugar if needed to balance the flavors. If the sauce is too thin, simmer for another minute to reduce. If too thick, add a splash of water. For a richer flavor, add a dash of sesame oil at the end.

   Tip: Always taste before serving and adjust seasoning to your preference.

8. Garnish and Serve: Transfer the Mongolian Beef to a serving plate. Garnish with chopped green onions for freshness and color. For extra flavor, sprinkle with toasted sesame seeds or a drizzle of sesame oil. Serve immediately with steamed rice or noodles. The dish is best enjoyed hot, with the beef juicy and the vegetables crisp.

   Tip: Serve with freshly steamed jasmine rice or hand-pulled noodles for an authentic experience.

9. Cleanup and Storage: Allow leftovers to cool before storing. Place in an airtight container and refrigerate for up to two days. To reheat, use a skillet over medium heat and add a splash of water to restore moisture. Avoid microwaving for best texture. Discard any leftovers that have an off smell or have been stored for more than two days.

   Tip: Mongolian Beef does not freeze well due to the sauce texture; consume within two days for best quality.

10. Extra Tips for Success:

    • Always slice beef against the grain for maximum tenderness.
    • Use fresh aromatics for the best flavor.
    • Do not overcook beef; remove from heat as soon as it is no longer pink.
    • If using a nonstick pan, reduce oil slightly.
    • For a spicier version, add a few dried red chilies or a pinch of chili flakes when stir-frying the aromatics.
    • Serve with freshly steamed jasmine rice or hand-pulled noodles for an authentic experience.
    • Use high heat throughout the stir-frying process for best texture.
    • Clean and dry all vegetables thoroughly to avoid excess moisture in the wok.
    • Always prepare and measure all ingredients before starting to cook (mise en place).
    • If you prefer a gluten-free version, use tamari instead of soy sauce and check all sauces for gluten content.
    • For extra umami, add a splash of dark soy sauce or a pinch of MSG.

💡 Tips

• Slice beef thinly for tenderness.
• Use hoisin sauce for authentic flavor.
• Do not overcook beef to keep it juicy.
• Serve with steamed rice or noodles.