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Learn how to make sweet and spicy Mongolian beef stir fry with tender marinated flank steak cooked in one skillet. This easy homemade takeout recipe is full of flavor, quick to make, and perfect for a weeknight dinner.
If you’re anything like me and you crave takeout—but you want it easy, satisfying, and a little healthier. That’s exactly why I love this Mongolian Beef Stir Fry so much! The flank steak is marinated to stay incredibly tender and juicy, and every bite is coated in a sweet and savory sauce that pairs perfectly with fluffy white rice. It’s the ultimate quick dinner that tastes indulgent but comes together in just 30 minutes.
One of the best parts about this Mongolian beef with flank steak is that it’s cooked all in one skillet, which means less mess and more flavor. Serve it over fluffy white rice, noodles, or even alongside steamed veggies for a complete meal. Whether you’re new to making stir fry at home or already love trying homemade Mongolian beef, this recipe is quick, flavorful, and one you’ll come back to again and again.
Why You’ll Love This Mongolian Beef Stir Fry
Quick & Easy: This 30 minute Mongolian beef stir fry is perfect for busy weeknights. With just one skillet and simple ingredients, you’ll have dinner on the table fast.
Marinated Flank Steak: The beef is made with flank steak, marinated to stay extra tender and juicy before being seared for maximum flavor. Prepping the marinade ahead makes this dish even easier for weeknight meals.
Better Than Takeout: This easy Mongolian beef recipe has the same sweet and savory flavors you love from your favorite restaurant, but made healthier at home.
Versatile & Customizable: Serve your Mongolian beef with flank steak over rice, noodles, or pair it with veggies for a balanced meal.
What You’ll Need
For the Marinated Flank Steak
- Flank steak
- Coconut aminos or soy sauce
- Mirin
- Rice vinegar
- Brown sugar
- Salt and pepper
- Baking soda
- Cornstarch
For the Mongolian Sauce
- Coconut aminos or soy sauce
- Mirin
- Oyster sauce
- Brown sugar
- Red pepper flakes
- Cornstarch slurry
For the Mongolian Beef Stir Fry
- Marinated flank steak
- Mongolian sauce
- Avocado oil
- Sweet onion
- Garlic
- Green onions
- Cooked white rice
Kitchen Tools Used For This Recipe
- Nonstick skillet
- Cutting board
- My favorite kitchen knife
- Mixing bowls
- Measuring cups and measuring spoons
- Rice Cooker
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How To Make Mongolian Beef Stir Fry
Prepare the Ingredients
To make the best Mongolian beef stir fry, start by prepping everything ahead of time so the cooking process is quick and seamless. Slice the flank steak against the grain into thin ¼-inch strips—this is the key to tender, melt-in-your-mouth beef. In a mixing bowl, combine the sliced steak with the marinade ingredients, then set aside while you prepare the rest of the dish. You may marinate the flank steak ahead of time, up to 3 hours. While the steak marinates, whisk together the sauce ingredients in a small bowl and chop the onions and garlic so everything is ready to go once you start cooking.
Cook the Flank Steak
Heat avocado oil in a large skillet over medium-high heat. Once hot, add the marinated flank steak in a single layer. Be careful not to overcrowd the pan—you may need to cook the steak in batches for the best sear. Sear the beef for 2–3 minutes on each side until caramelized and cooked to your desired doneness. Transfer the cooked beef to a plate and set aside.
Cook the Aromatics and Vegetables
In the same skillet, add a touch more avocado oil if needed, then toss in the minced garlic and the white parts of the green onions. Sauté for 1–2 minutes until fragrant. Next, add the sliced sweet onion and cook for about 5 minutes, stirring occasionally, until softened and lightly golden. This step builds the aromatic base of the stir fry and enhances the savory flavor of the beef.
Combine Everything Together
Return the seared beef to the skillet along with the prepared sauce and the green parts of the green onions. Stir well to coat the meat and vegetables evenly. Let the mixture simmer for 1–2 minutes until the sauce thickens slightly and clings to every piece of beef. The end result is a glossy, flavorful Mongolian beef that tastes just like your favorite takeout but comes together in one skillet in under 30 minutes.
Serving the Mongolian Beef Stir Fry
This flavorful Mongolian beef stir fry is best enjoyed hot and fresh, served over a bowl of fluffy steamed white rice that soaks up all the savory-sweet sauce. For a twist, you can also pair this easy Mongolian beef recipe with noodles such as lo mein, udon, or even rice noodles for a heartier meal. If you’re looking to boost the veggie content, add extra stir-fried vegetables like broccoli, snap peas, or bell peppers to make the dish more filling and colorful. However you serve it, this tender and flavorful Mongolian beef with flank steak makes the perfect weeknight dinner that’s quick, satisfying, and customizable to your taste.
Recipe Tips
When making this Mongolian beef stir fry, there are a few tips that will help you get the best results every time:
- Don’t skip the baking soda: It may seem like a small step, but baking soda helps tenderize the flank steak, keeping the beef soft and flavorful once cooked.
- Cook in an even layer: Be sure not to overcrowd the pan. Cooking the beef in batches if needed ensures each piece gets a beautiful sear and caramelization, which adds incredible flavor.
- Marinate for maximum flavor: If you have time, marinate the beef for up to 3 hours to deepen the flavor and tenderize the meat even further. Short on time? A quick 10–15 minute marinade will still give you delicious results.
Alternatives & Substitutions
- Different proteins: While flank steak is the traditional choice for this easy Mongolian beef recipe, you can also use skirt steak, sirloin, ribeye steak, or even chicken for a slightly different but equally tasty variation.
- Spice level: Adjust the heat to your liking by increasing or omitting the red pepper flakes. For extra spice, toss in fresh red chilies when sautéing the garlic and onions.
- Onion swap: Sweet onions give the stir fry a mild, balanced flavor, but yellow onions work just as well if that’s what you have on hand.
Storage
If you have leftovers, store your Mongolian beef with flank steak in an airtight container in the refrigerator for up to 3 days. Reheat gently in a skillet over medium heat to keep the beef tender, or microwave in short intervals. Serve again with fresh rice, noodles, or stir-fried vegetables for a quick and satisfying meal.
More Asian-Inspired Dinner Recipes You’ll Love
- Easy Orange Chicken with a Sweet and Tangy Glaze
- Crispy Korean Fried Chicken in the Air Fryer
- Sticky Sweet Chili Chicken
- Peanut Noodles with Chili Shrimp and Quick Pickled Cucumbers
- Gochujang Chicken Rice Bowl
30-Minute Mongolian Beef Stir Fry (Better Than Takeout!)
Equipment
Ingredients
Beef Marinade
- 1 ½ lbs flank steak sliced ¼ inch, against the grain
- 2 tbsp coconut aminos or soy sauce
- 1 tbsp mirin
- 1 tbsp rice vinegar
- 1 tbsp brown sugar
- ¼ tsp salt
- ¼ tsp black pepper
- ½ tsp baking soda
- 2 tbsp cornstarch
Mongolian Sauce
- 3 tbsp coconut aminos or soy sauce
- 1 tbsp oyster sauce
- 1 tbsp mirin
- 2 tbsp brown sugar
- 1 tsp red pepper flakes
- ¼ cup water mixed with 1 tsp cornstarch to make cornstarch slurry
Stir Fry Ingredients
- 2 tbsp avocado oil or any neutral cooking oil
- 1 sweet onion sliced
- 5 garlic cloves minced
- 2 tbsp white parts of green onion minced
- ½ cup green parts of green onion chopped
For Serving
- cooked white rice
Instructions
- Start by slicing the flank steak against the grain into thin ¼-inch strips. In a mixing bowl, combine the steak with the marinade ingredients, tossing well to coat. Set aside to marinate while you prep the rest of the ingredients, or refrigerate for up to 3 hours ahead of time for extra flavor. Next, whisk together the sauce ingredients in a small bowl and set aside. Slice the sweet onion, mince the garlic and the white parts of the green onions, and chop the green tops of the green onions.
- Heat avocado oil in a large skillet over medium-high heat. Once the oil is hot, add the marinated flank steak in a single layer. Avoid overcrowding the pan—you may need to cook in batches for the best sear. Sear the beef for 2–3 minutes per side, until it’s cooked to your desired doneness and develops a nice char and caramelization. Transfer the cooked beef to a plate and set aside.
- In the same skillet, add the minced garlic and the white parts of the green onion. Sauté for 1–2 minutes, just until fragrant. Add the sliced sweet onion and continue cooking for about 5 minutes, until softened and lightly golden. If the skillet looks a little dry, add a touch more avocado oil as needed.
- Add the seared beef back into the skillet along with the prepared sauce and the green parts of the green onion. Stir well to combine, coating the beef and vegetables evenly. Let everything simmer for 1–2 minutes, just until the sauce slightly thickens and clings to the beef. Serve immediately over white rice.
