Slow Cooker Mongolian Beef (Printable)

Tender beef in rich, savory-sweet sauce with Asian-inspired flavors. Perfect for family dinners.

# What You Need:

→ Beef

01 - 2 pounds flank steak, thinly sliced against the grain

→ Sauce

02 - 3/4 cup low-sodium soy sauce
03 - 1/2 cup dark brown sugar, packed
04 - 1/2 cup water
05 - 1/4 cup hoisin sauce
06 - 1 tablespoon sesame oil
07 - 1 tablespoon freshly grated ginger
08 - 5 cloves garlic, minced
09 - 1/2 teaspoon freshly ground black pepper
10 - 1/4 teaspoon crushed red pepper flakes (optional, for heat)

→ Thickener

11 - 1/4 cup cornstarch

→ Vegetables & Garnish

12 - 5 green onions, sliced (white and green parts separated)
13 - 1 tablespoon toasted sesame seeds
14 - Steamed white or brown rice, for serving

# Directions:

01 - In a large bowl, toss the sliced flank steak with cornstarch until all pieces are evenly coated. Shake off any excess.
02 - Add the beef to the slow cooker.
03 - In a separate bowl, whisk together soy sauce, brown sugar, water, hoisin sauce, sesame oil, ginger, garlic, black pepper, and crushed red pepper flakes.
04 - Pour the sauce over the beef in the slow cooker and toss gently to combine.
05 - Scatter the white parts of the green onions over the top.
06 - Cover and cook on low for 4 hours, or until the beef is tender and the sauce has thickened slightly.
07 - Stir in the sliced green onion tops and cook for an additional 10 minutes.
08 - Serve hot over steamed rice, garnished with toasted sesame seeds and extra green onions if desired.

# Expert Tips:

01 -
  • The beef becomes so tender you could cut it with a spoon, no fancy knife skills required
  • That sauce creates this incredible sticky coating that clings to every single piece
  • Most of the work happens in the slow cooker while you go about your day
02 -
  • Resist the urge to lift the lid too often—every time you do, you add 15-20 minutes to the cooking time
  • The sauce might look thin at first, but it thickens beautifully as it cooks and the cornstarch works its magic
  • Slicing the beef when it's partially frozen makes it so much easier to get those thin, even slices
03 -
  • Flank steak can be pricey, but it's worth it here—skirt steak works too if you can find it on sale
  • The beef holds up beautifully and tastes even better the next day, making it perfect for meal prep
  • If you're sensitive to heat, start with half the red pepper flakes and add more at the end if desired

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