Mongolian beef is a Chinese-American takeout-style stir-fry of tender beef coated in a glossy, sweet-savory sauce with soy, garlic, and ginger; despite its name, it is not a traditional dish from Mongolia. This easy sauce comes together in one pan and clings to thinly sliced beef, while a little vinegar keeps the sweetness balanced.
Ingredients
- 1 lb flank steak (454 g), trimmed and sliced thinly across the grain
- 2 tbsp cornstarch (16 g), divided
- 2 tbsp neutral oil, such as canola or avocado oil (30 ml), divided
- 1/3 cup low-sodium soy sauce (80 ml)
- 1/3 cup water (80 ml), divided
- 1/3 cup packed light brown sugar (about 67 g)
- 1 tbsp unseasoned rice vinegar (15 ml)
- 3 garlic cloves (about 9 g), finely minced
- 2 tsp finely grated fresh ginger (10 g)
- 1/4 tsp red pepper flakes (about 0.5 g), optional
- 2 scallions (about 30 g), thinly sliced, for serving
- 1 tsp toasted sesame seeds (3 g), optional
Instructions
- Slice the steak across the grain into strips about 1/4 inch (6 mm) thick. Pat the strips dry with paper towels, then toss them with 1 tablespoon (8 g) of the cornstarch until lightly coated. Let them stand while you mix the sauce; this short pause helps the coating adhere.
- In a small bowl, whisk the soy sauce, brown sugar, rice vinegar, and 1/4 cup (60 ml) of the water until the sugar is mostly dissolved. In a second small bowl, stir the remaining 1/4 cup (60 ml) water with the remaining 1 tablespoon (8 g) cornstarch until smooth. Keep this slurry nearby; cornstarch settles quickly, so stir it again just before using.
- Heat 1 tablespoon (15 ml) of the oil in a large skillet or wok over medium-high heat until it shimmers. Cook the beef in two batches so the pan stays hot and the strips brown rather than steam. Spread each batch into a single layer, turn the pieces as they brown, and transfer them to a clean plate. The strips should be nearly cooked through, but the safe endpoint matters more than color: check the thickest pieces with a food thermometer. USDA FSIS lists 145°F (63°C) with a 3-minute rest as the safe minimum for whole cuts of beef. Rest the cooked beef for 3 minutes while you make the sauce.
- Reduce the heat to medium and add the remaining 1 tablespoon (15 ml) oil. Add the garlic, ginger, and optional red pepper flakes. Stir for about 30 seconds, just until fragrant; if the garlic begins to darken, move straight to the next step so it does not turn bitter.
- Pour the soy mixture into the pan and bring it to a gentle simmer, stirring to dissolve any browned bits. Stir the cornstarch slurry again, then stream it into the sauce while stirring. Simmer for 1 to 2 minutes, until the sauce looks shiny and lightly thickened. It should coat a spoon but still flow easily; it will thicken a little more when it meets the beef.
- Return the rested beef and any juices on the plate to the pan. Toss for 1 to 2 minutes, until every strip is coated and hot. If the sauce becomes too thick, loosen it with water 1 tablespoon (15 ml) at a time. If it looks thin, simmer briefly while stirring rather than adding more dry cornstarch. Sprinkle with scallions and sesame seeds, if using, and serve promptly.
Tips
- Slice across the grain. Look for the long muscle fibers in the steak and cut across them, not parallel to them. Shorter fibers make the finished strips easier to bite. If the steak is difficult to slice thinly, put it in the freezer for 15 to 20 minutes first; it should firm up without freezing solid.
- Keep the pan uncrowded. A crowded skillet releases moisture and boils the beef instead of browning it. Cook in batches, and give the pan a moment to heat back up between batches. A wide skillet works better than a small saucepan for this recipe.
- Choose your soy sauce thoughtfully. Low-sodium soy sauce gives you more control over saltiness. Regular soy sauce works, but the result will be saltier, so avoid adding extra salt and consider replacing a tablespoon of soy sauce with water. Tamari can replace soy sauce in equal measure and usually gives a similarly savory result; check its label if gluten avoidance is important.
- Adjust thickness only after simmering. The sauce thickens as the cornstarch cooks and again as it cools. A short simmer is usually enough. If it turns gluey, stir in a splash of water; if it remains watery, simmer another 30 seconds and reassess before adding anything else.
Serving Suggestions
Serve the beef and sauce over steamed jasmine rice, medium-grain rice, or brown rice so the grains catch the glossy sauce. For a takeout-style plate, add steamed broccoli, sliced carrots, or snap peas on the side. You can also spoon the beef over noodles, but choose noodles with a fairly plain flavor so they do not compete with the salty-sweet sauce. A simple cucumber salad or lightly dressed greens add freshness alongside the rich stir-fry.
For a meal with more vegetables, stir-fry broccoli florets, bell pepper strips, or snow peas before cooking the beef. Transfer the vegetables to a plate, cook the beef as directed, then return the vegetables when you add the sauce-coated meat. This keeps the pan from getting overcrowded and helps the vegetables stay distinct rather than becoming soft in the sauce. Keep additional soy sauce or chili oil at the table so diners can adjust their own portions.
Variations
Make it less sweet: Reduce the brown sugar to 1/4 cup (about 50 g). The sauce will taste more savory and less like the sweet glaze commonly served with takeout-style Mongolian beef. Avoid cutting the sugar to zero if you want a rounded sauce; sweetness helps balance the soy and ginger.
Add a little heat: Increase the red pepper flakes to 1/2 teaspoon (about 1 g), or finish with chili crisp at the table. Chili crisp adds oil and crunchy aromatics, so use a small amount at first and adjust after tasting. For a milder sauce, simply leave out the flakes.
Use a different cut: Flat iron or sirloin can stand in for flank steak. Slice either cut thinly across the grain and trim away any tough connective tissue. Avoid thick strips, which take longer to cook and are more likely to overcook on the outside before becoming tender.
Make it without beef: Use firm tofu, cut into cubes and patted dry, or a meaty mushroom such as king oyster. Brown the tofu or mushrooms in batches, then coat them in the sauce. This changes the dish’s texture and savory flavor, but the same sauce method works. For a fully vegetarian version, choose a vegetarian mushroom-based sauce or soy sauce rather than any animal-based seasoning.
Try a deeper savory note: Stir 1 teaspoon (5 ml) of toasted sesame oil into the finished sauce, rather than using it as the main frying oil, since its aroma can fade or scorch at high heat. A small splash of Shaoxing wine is also used in some stir-fry versions, though it is not essential; if unavailable, omit it rather than buying a bottle just for this sauce. Mirin is a possible substitute, but it is sweeter, so reduce the brown sugar slightly.
Storage and Reheating
Refrigerate leftover beef and sauce within 2 hours of cooking in a shallow, covered container. It keeps for 3 to 4 days in the refrigerator. Store it with rice separately when possible; rice absorbs sauce during storage, and keeping the components apart makes it easier to reheat the beef without drying it out. Do not leave the cooked beef at room temperature for more than 2 hours.
For best texture, reheat a portion in a skillet over medium heat with 1 to 2 tablespoons (15 to 30 ml) of water. Stir gently until steaming hot, adding another small splash of water if the sauce has become thick or sticky. Reheat leftovers to 165°F (74°C), checking the center with a food thermometer. A microwave also works: cover loosely, heat in short intervals, and stir between intervals so the beef warms evenly. Avoid repeated cooling and reheating.
Freeze portions in a sealed freezer-safe container for up to 2 months for best quality. Thaw overnight in the refrigerator, then reheat to 165°F (74°C). The beef may be a little less tender after freezing, and the sauce can separate slightly; stirring with a spoonful of water while reheating usually brings it back together. Freeze rice separately if you want to preserve its texture.
Frequently Asked Questions
What is Mongolian beef sauce made of?
This version combines soy sauce, brown sugar, water, rice vinegar, garlic, and ginger. Cornstarch thickens it into a glossy coating. Recipes differ by restaurant and household: some are sweeter, some use more ginger or chili, and some include ingredients such as scallions or cooking wine. The goal here is a balanced sauce that clings to the beef without becoming syrupy.
Is Mongolian beef actually from Mongolia?
Mongolian beef as commonly served in North American restaurants is a Chinese-American dish, not a traditional Mongolian recipe. The name is associated with restaurant-style cooking, and the dish has variations rather than a single definitive formula. This recipe follows the familiar sweet-savory stir-fry style without claiming to represent all regional or family versions.
Can I make the sauce ahead of time?
Yes. Whisk together the soy sauce, sugar, vinegar, and water up to 3 days ahead and refrigerate it in a covered container. Keep the garlic and ginger separate until cooking for a fresher aroma. Mix the cornstarch with water just before adding it to the hot pan, because a prepared slurry separates as it sits. Stir the refrigerated sauce before pouring it into the skillet.
Why is my sauce too thin or too thick?
A thin sauce may need another brief simmer so the cornstarch has time to thicken it. Check that the slurry was smooth and stirred immediately before it went into the pan. A sauce that is too thick may have simmered too long or reduced too much; thin it with water a tablespoon at a time. Remember that the sauce thickens further as it cools and coats the beef.
Can I use bottled Mongolian beef sauce?
You can, but its sweetness, salt level, and thickness vary by product, so it will not taste exactly like this recipe. If using a bottled sauce, start with the amount suggested on its label and taste before adding extra soy sauce or sugar. The homemade version lets you control those ingredients and avoids needing a separate prepared sauce.
Can I make this recipe gluten-free?
Use tamari or a certified gluten-free soy sauce, and check the labels on the cornstarch and any other packaged ingredients. Traditional soy sauce is commonly made with wheat, so ordinary soy sauce is not a safe substitute for someone who needs to avoid gluten. The flavor of tamari is close, though its saltiness varies, so taste the sauce before serving.
Related
- Mongolian Dumplings: Buuz Recipe and Steaming Tips
- Mongolian Beef Recipe with Onions for a Quick Stir-Fry
- Mongolian Pork Tenderloin With a Glossy Ginger Sauce
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Safety notes: safe minimum internal temperatures from USDA FSIS; raw and undercooked fish guidance from the U.S. FDA. Food safety notes
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