Tender Mongolian Beef Delight

This slow cooker Mongolian beef transforms ordinary flank steak into a restaurant-quality dish with minimal effort. The meat becomes incredibly tender while soaking up a sweet and savory sauce that rivals your favorite takeout spot.

I discovered this recipe during a particularly busy work week when I needed meals that could cook while I was away. My family was so impressed they requested it weekly, and it's now our go-to for entertaining guests who always ask for the recipe.

Ingredients

• Flank steak: Cut against the grain ensures tenderness in every bite. Look for meat with even marbling for best results
• Cornstarch: Creates a velvet-like texture on the beef while helping to thicken the sauce
• Toasted sesame oil: Adds authentic Asian flavor. Always choose dark sesame oil for more robust taste
• Minced garlic and ginger: Form the aromatic foundation. Fresh is significantly better than pre-packaged
• Low sodium soy sauce: Allows you to control the saltiness while providing rich umami flavor
• Brown sugar: Balances the savory elements with necessary sweetness. Dark brown adds more depth
• Water: Helps create the perfect sauce consistency without diluting flavor
• Green onions: Provide fresh contrast and visual appeal. Select firm stalks with bright color

Step-by-Step Instructions

Prepare the Beef:

Slice flank steak thinly against the grain into quarter-inch strips. This cutting technique is crucial for tenderness. Toss with cornstarch in a large mixing bowl, ensuring each piece is thoroughly coated. The cornstarch will create a protective barrier and help thicken the final sauce.

Layer Ingredients:

Place the coated beef pieces in your slow cooker insert. Avoid stacking too high in any one area for even cooking. Add the sesame oil, minced garlic, minced ginger, soy sauce, brown sugar, and water. Gently stir to combine everything without removing too much cornstarch from the beef.

Slow Cook to Perfection:

Cover the slow cooker with its lid and set to HIGH for 2-3 hours or LOW for 4-5 hours. The longer cooking time on LOW produces more tender results if you have the time. Avoid lifting the lid during cooking as this releases heat and extends cooking time.

Finishing Touches:

Once the beef is fork tender, stir the mixture well to incorporate any sauce that may have separated. Taste and adjust seasonings if needed. Fold in sliced green onions, reserving some for garnish. The residual heat will slightly wilt the onions while maintaining their fresh flavor.

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I particularly love how the brown sugar caramelizes slightly during cooking, creating little pockets of sweetness throughout the dish. My grandmother first introduced me to Mongolian beef during childhood visits to her favorite Chinese restaurant, but this homemade version brings back those memories without the restaurant price tag.

Storage and Reheating

This Mongolian beef keeps beautifully in an airtight container in the refrigerator for up to 4 days. The flavors actually deepen overnight, making leftovers sometimes even better than the original meal. When reheating, add a splash of water if the sauce has thickened too much, and warm gently on the stovetop or microwave until just heated through to prevent the meat from toughening.

Simple Substitutions

While flank steak is traditional, skirt steak or sirloin work wonderfully too. For a leaner option, boneless beef chuck can be used with a slightly longer cooking time. Coconut aminos make an excellent replacement for soy sauce for those avoiding gluten or soy. Maple syrup can substitute for brown sugar if preferred, though the flavor profile will shift slightly. For a spicy variation, add 1-2 teaspoons of sriracha or red pepper flakes to the sauce ingredients.

Serving Suggestions

The classic pairing for Mongolian beef is steamed white rice, which provides the perfect neutral canvas for the flavorful sauce. For a lower carb option, cauliflower rice works beautifully. Steamed broccoli or snap peas add color and nutrition while soaking up the delicious sauce. For a complete experience, serve with hot and sour soup as a starter and fortune cookies for a fun finish. Chopsticks optional but recommended for the full experience.

Recipe FAQs

→ What cut of beef works best for Mongolian beef?

Flank steak is the traditional choice as it becomes tender when slow-cooked and has excellent flavor. However, you could substitute skirt steak, sirloin, or even chuck roast (though cooking time may need adjustment for chuck). The key is slicing thinly against the grain regardless of which cut you choose.

→ Why is coating the beef in cornstarch important?

Cornstarch serves multiple purposes: it creates a light protective coating that prevents the beef from overcooking, helps thicken the sauce during slow cooking, and gives the finished dish that characteristic velvety texture found in many Asian beef dishes. Don't skip this step for best results.

→ Can I make this dish less sweet?

Absolutely. The 1/3 cup of brown sugar creates the signature slightly sweet flavor of Mongolian beef, but you can reduce it to 2-3 tablespoons if you prefer a less sweet, more savory profile. The dish will still have plenty of flavor from the soy sauce, garlic, and ginger.

→ What should I serve with Slow Cooker Mongolian Beef?

Traditional accompaniments include steamed white rice or noodles to soak up the delicious sauce. For a complete meal, add steamed broccoli, bell peppers, or a simple Asian slaw. Some people also enjoy adding extra vegetables like sliced carrots or snow peas during the last 30 minutes of cooking.

→ How can I store leftovers?

Leftover Mongolian beef stores beautifully in an airtight container in the refrigerator for 3-4 days. The flavors often deepen overnight, making it even more delicious the next day. Reheat gently in a microwave or in a skillet over medium-low heat, adding a splash of water if needed to loosen the sauce.

→ Can this dish be frozen?

Yes, this Mongolian beef freezes well for up to 3 months. Cool completely before transferring to freezer-safe containers. For best texture, thaw overnight in the refrigerator before reheating. The sauce may need to be thinned slightly with water when reheating, and a fresh sprinkle of green onions will brighten it up.