Slow Cooker Mongolian Beef Recipe

Slow Cooker Mongolian makes weeknight dinners easy by delivering tender, saucy beef with very little hands-on time. If you need a reliable, family-friendly main you can set and forget, this method fits busy evenings and casual dinners.

Many people search for this dish because it balances sweet and savory flavors while using simple pantry ingredients. It also solves the need for a make-ahead dinner that still tastes fresh when served.

Why Make This Recipe

This recipe is straightforward and uses common ingredients like brown sugar and low sodium soy sauce, so you won’t need specialty items. You only need to toss the meat with cornstarch, add the sauce, and let the slow cooker do the work.

Cooking in a slow cooker yields consistently tender results from flank steak and frees you to prepare sides or relax. The hands-off timeframe—2–5 hours depending on heat setting—makes it practical for workday afternoons.

The outcome is a glossy, slightly thickened sauce coating pieces of beef that pull apart easily. You can scale the recipe up without changing technique, which makes it useful for feeding a crowd.

How to Make Slow Cooker Mongolian Beef

The approach focuses on a simple starch-based coating and a balanced sauce so the beef stays moist and the sauce clings. Coating the beef with cornstarch helps thicken the sauce and creates a silky mouthfeel.

Cooking on low for several hours lets connective tissue in the flank steak break down slowly, producing tender slices rather than dry, overcooked meat. Adding green onions at the end preserves a fresh bite and color contrast.

Ingredients

• 1 1/2 pounds flank steak (thinly sliced against the grain)
• 1/4 cup cornstarch
• 1 tablespoon toasted sesame oil
• 1 teaspoon minced garlic
• 1 teaspoon minced ginger
• 1/2 cup low sodium soy sauce
• 1/3 cup brown sugar
• 1/2 cup water
• 1/2 cup green onions (for garnish)

Directions

1. Toss the flank steak with cornstarch in a mixing bowl until evenly coated.
2. Place the coated steak in a slow cooker and add sesame oil, garlic, ginger, soy sauce, brown sugar, and water. Stir gently to combine.
3. Cover and cook on HIGH for 2-3 hours or LOW for 4-5 hours until beef is tender.
4. Stir in green onions just before serving.

How to Serve Slow Cooker Mongolian Beef

Serve the beef over steamed white rice, brown rice, or a bed of quick-cooked noodles to catch the sauce. For a lower-carb option, spoon it over cauliflower rice.

Garnish with the green onions for a bright finish and sprinkle of sesame seeds if you have them. Offer extra soy sauce or a side of chili oil for guests who prefer more salt or heat.

Pair the dish with a crisp cucumber salad, steamed broccoli, or simple stir-fried greens to balance the sweetness. For drinks, a light beer or green tea complements the flavors without overpowering them.

How to Store Slow Cooker Mongolian Beef

Cool the beef to room temperature before refrigerating to prevent condensation that can dilute the sauce. Store in an airtight container in the refrigerator for up to 4 days.

To freeze, portion the beef into meal-sized containers and freeze for up to 3 months. Thaw overnight in the refrigerator before reheating.

Reheat gently on the stove over low heat, stirring often and adding a tablespoon of water if the sauce has thickened too much. Avoid high heat which can dry the meat.

Tips to Make Slow Cooker Mongolian Beef

Follow these tips to improve texture and flavor.

• Use flank steak thinly sliced and cut against the grain for more tender bites.
• Pat the steak dry before tossing with cornstarch so the coating adheres better.
• Do not over-salt; the low sodium soy sauce gives control and prevents oversalting.
• Brown sugar and soy sauce balance each other; adjust brown sugar if you prefer less sweetness.
• Stir gently when combining ingredients to keep the cornstarch coating intact.
• Add green onions garnish just before serving to retain color and crunch.
• If sauce is too thin at the end, remove lid and cook on HIGH for 10–15 minutes to reduce.
• For a deeper flavor, sear the coated steak briefly in a hot pan before adding to the slow cooker (optional).

Common Mistakes to Avoid

The most common mistake is slicing the flank steak with the grain, which yields chewier pieces. Slice against the grain and thinly for the best tenderness.

Another mistake is adding the green onions too early; they will overcook and lose color. Add them at the end for brightness and texture.

Variations

If you prefer a touch of heat, add 1/4–1/2 teaspoon crushed red pepper flakes to the sauce. For a gluten-free version, swap tamari or a gluten-free soy sauce for the low sodium soy sauce. You can substitute sirloin tip for flank steak if needed, though thin slicing remains important.

FAQs

What cut of beef is best for this recipe?
Flank steak is preferred for its flavor and texture when thinly sliced against the grain.

Can I use frozen beef?
No. Use fully thawed beef so the cornstarch coating and sauce absorb properly and you get even cooking.

How do I thicken the sauce if it’s watery?
Cook uncovered on HIGH for 10–15 minutes to reduce, or whisk 1 teaspoon cornstarch with 1 tablespoon cold water and stir in, then cook briefly.

Is this recipe spicy?
No. The base recipe is sweet and savory. Add chili flakes or sriracha if you want heat.

Can I make this on the stovetop instead?
Yes. Simmer the sauce in a skillet and add seared steak for a faster version, but adjust cornstarch to control thickness.

How long will leftovers last?
Stored in the refrigerator in an airtight container, leftovers keep for up to 4 days.

Conclusion

This slow-cooker method gives reliably tender results and a sticky, flavorful sauce that’s easy to scale for family meals. For the original inspiration and a similar slow cooker approach, see Dinner at the Zoo’s Slow Cooker Mongolian Beef recipe.

More beef recipe :
Cheesy Ground Beef Melt Easy Skillet Sandwich