Slow Cooker Mongolian Beef Recipe

Slow Cooker Mongolian Beef is for those nights when you want something cozy and takeout-level tasty without leaving home. I grab simple pantry staples, toss everything into the slow cooker, and let it work while I get on with my day. If you love set-it-and-forget-it dinners, you’ll probably enjoy exploring more ideas on my favorite crockpot creations page. The texture gets silky, the sauce turns glossy, and dinner feels special with almost no stress. Plus, the leftovers are amazing for next-day lunches. Let me show you how I make it, with a few tricks to keep the sauce perfect and the beef extra tender.

Why This Slow Cooker Mongolian Beef Version Beats Takeout

It tastes like your favorite restaurant, but you control the ingredients. That means you can keep sodium reasonable, choose the best cut of beef, and balance sweetness exactly how you like it. You also skip frying in oil, so it feels a bit lighter yet still rich and satisfying. The slow cooker lets the flavors blend gently, and the sauce picks up that deep soy, garlic, and ginger vibe we all love. With rice and a quick veggie, dinner is ready without a last-minute scramble.

Ingredients for Slow Cooker Mongolian Beef

What you will need

• Flank steak, thinly sliced against the grain
• Low-sodium soy sauce
• Brown sugar
• Minced garlic
• Fresh ginger, grated
• Beef broth
• Cornstarch
• Sesame oil
• Neutral oil for quick sear or skillet bloom (optional)
• Green onions for garnish
• Red pepper flakes or sriracha, if you like mild heat

That’s the base. After that, feel free to toss in vegetables like broccoli or carrots near the end so they stay crisp-tender. I also keep extra broth on hand in case I want to thin the sauce just a bit.

Key Ingredients (Flank Steak, Soy Sauce, Brown Sugar, Garlic, Ginger)

Flank steak slices into neat thin ribbons and becomes tender in the slow cooker. Low-sodium soy keeps the sauce balanced and not overly salty. Brown sugar helps create that signature glossy coating and a slight caramel vibe. Garlic and ginger are the flavor heroes that make the sauce smell incredible once it warms up. If you only measure one thing carefully, make it the soy and sugar ratio so the finish is not too sweet or too salty.

Sauce Ingredients for Classic Mongolian Flavor

My sauce is a simple mix of soy sauce, brown sugar, beef broth, sesame oil, garlic, and ginger. A touch of cornstarch thickens everything at the end so it’s silky and coats every bite. If you prefer more depth, add a spoonful of hoisin or a splash of rice vinegar. I like keeping it clean and classic so the beef shines. Taste and adjust at the end instead of early on, since flavors concentrate as they cook.

Optional Add-Ins (Broccoli, Carrots, Snow Peas, Bell Peppers)

Veggies are totally welcome. Broccoli florets, sliced carrots, snow peas, or bell peppers turn it into a full one-pot meal. Add firmer vegetables in the last hour on low or last 30 minutes on high so they do not go mushy. If you love a complete bowl dinner, load up the veggies generously. It keeps the dish colorful and adds a bit of crunch for contrast.

Ingredient Substitutions & Diet-Friendly Swaps

Use tamari for a gluten-free sauce. Coconut aminos works if you need soy-free, but reduce the brown sugar a bit since coconut aminos is sweeter. Swap flank steak with sirloin if you have it. Arrowroot can replace cornstarch for thickening, and you can use light brown sugar or even a little honey if that’s what you keep in your pantry. For less sodium, use low-sodium broth and low-sodium soy, then season to taste at the end.

How to Make Slow Cooker Mongolian Beef

Step-by-step game plan

Slice the flank steak thinly against the grain. Whisk soy sauce, brown sugar, beef broth, minced garlic, grated ginger, and a tiny drizzle of sesame oil. Add the beef to the slow cooker and pour the sauce over the top. Cook on low until tender. When it’s close to done, stir a cornstarch slurry into the sauce and let it thicken until glossy. Garnish with green onions and serve hot.
If you love hearty beef meals, you might also enjoy this cozy bowl of comfort: Beef Stew in a Crock Pot. It’s another simple set-it-and-enjoy dinner for busy nights.

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Tips for the Best Mongolian Beef in the Slow Cooker

Flavor boosters that make a difference

For deeper flavor, quickly sear half the beef in a hot skillet before transferring to the slow cooker. Let the soy, sugar, garlic, and ginger bloom in the pan for 30 seconds too. Keep the slices thin and even so they cook at the same pace. Taste the sauce after cooking and adjust salt, sweetness, or heat. If it’s too strong, add a splash of broth; if it needs pop, add a tiny splash of rice vinegar.

Best Cut of Beef for Mongolian Beef

Flank steak is my top pick because it slices thin and turns tender as it simmers. You can use sirloin or flat iron with good results. The key is slicing against the grain and keeping the pieces even. A quick tip: chill the steak in the freezer for 15 minutes before slicing so you can get clean, thin strips. Pat them dry to avoid diluting the sauce.

How to Get Extra-Tender Beef

Slice against the grain and avoid overcooking. The slow cooker makes the beef soft, but if it goes too long it can start to shred. Keep the sauce just barely thickened, not gluey. A short sear locks in flavor, while the slow simmer softens the meat. If the beef is tough, it likely needs a little more time or the slices were too thick.

Preventing the Sauce from Getting Too Thick or Too Thin

If the sauce is too thick, stir in a bit of warm broth and let it loosen in the slow cooker for a few minutes. If it’s too thin, whisk a small cornstarch slurry and add it slowly, stirring until it coats the spoon. Remember the sauce continues to thicken slightly as it cools. It should cling to the beef and not pool like soup. Aim for that glossy, velvety look.

A Few Easy Variations of Slow Cooker Mongolian Beef

Turn up the heat with red pepper flakes, sriracha, or a thinly sliced fresh chili. Add orange zest and a little juice for a brighter spin. Swap half the soy sauce with teriyaki for a sweeter glaze. For a chicken twist, you might like this bright and cozy slow cooker option: Slow Cooker Lemon Herb Chicken.

What to Serve with Slow Cooker Mongolian Beef

I keep it simple with steamed white rice or jasmine rice. Stir-fried veggies or quick sautéed greens add freshness. If you want to start dinner with a warm bowl, this comforting soup pairs nicely: Crockpot Beef and Vegetable Soup. It feels like a full restaurant spread, but everything is easy and homey. Garnish with sliced green onions and a sprinkle of sesame seeds for a nice finish.

Best Sides: Rice, Noodles, Quinoa, or Cauliflower Rice

• White rice or jasmine rice for classic comfort
• Brown rice for a nutty, hearty base
• Rice noodles or lo mein for slurpable fun
• Quinoa if you want extra protein
• Cauliflower rice for a lighter plate

My trick is to cook the side while the sauce thickens in the slow cooker. Everything lands on the table hot and ready at the same time. Leftover rice reheats beautifully with the saucy beef the next day.

Slow Cooker Settings & Cooking Time Guide

Cook thin-sliced flank steak on low for 4 to 5 hours, or on high for 2 to 3 hours. Check at the early mark since every slow cooker runs a little different. Add cornstarch slurry during the last 20 to 30 minutes so the sauce thickens without turning pasty. If you add vegetables, put them in during the last hour on low or last 30 minutes on high. Keep the lid on to maintain steady heat.

Make-Ahead, Storage & Reheating Instructions

Plan once, eat twice

Slice the steak a day ahead and whisk the sauce in a jar, then combine everything in the morning. Store leftovers in an airtight container in the fridge for up to 4 days. Reheat gently on the stove with a splash of broth to loosen the sauce, or use the microwave in short bursts. It also freezes well for up to 2 months. I like to freeze in single-serve portions for quick lunches.

Common Mistakes & How to Fix Them

Too sweet? Add more soy and a squeeze of lime or a splash of rice vinegar. Too salty? Stir in extra brown sugar and broth to balance it out. Sauce not thickening? Your slow cooker might be too cool, so give it more time and keep the lid on. Beef feels dry? It may be overcooked or sliced too thin. Next time, shave a bit off the cook time or slice a touch thicker.

How to Prevent Burning in the Slow Cooker

Keep enough liquid in the pot and do not use the high setting for too long. Avoid piling all the sugar at the bottom where it can caramelize. Stir once mid-cook if your slow cooker tends to run hot. If using a smaller slow cooker, reduce the heat and check early. Thickening should always happen at the end, not the start.

Can I Use Chicken Instead of Beef?

Yes. Use boneless skinless chicken thighs, slice them into strips, and follow the same method. Cook time will be similar, but check early for doneness. The sauce pairs beautifully with chicken and still feels indulgent. If you want a different beef dish with potatoes, try these buttery bites: Crockpot Garlic Butter Beef Bites with Potatoes.

Nutritional facts overview

This dish is rich but you can adjust it to your needs. Use low-sodium soy, trim extra fat from the steak, and serve over cauliflower rice if you want to lighten things up. A typical serving with rice offers a good protein boost, moderate fat, and a sweet-savory sauce. Portion size matters most here. Balance your plate with a big scoop of veggies for fiber and color.

Common Questions

Do I need to sear the beef first? Nope, but a quick sear adds flavor. If you are short on time, skip it and it will still be great.
Can I use regular soy sauce? Yes, just taste at the end. If it is too salty, add a splash of broth and a pinch of sugar.
How thin should I slice the flank steak? About 1/4 inch or thinner. Freeze for 10 to 15 minutes first for cleaner slices.
When should I add the cornstarch slurry? During the last 20 to 30 minutes so the sauce thickens without clumping.
Can I make it spicier? Absolutely. Add red pepper flakes, a squeeze of sriracha, or fresh chili slices.

A cozy wrap-up for hungry nights

There you have it. A simple path to a saucy, tender bowl that tastes like takeout but feels homemade. Keep the soy and sugar balanced, slice the beef thin, and finish with that quick slurry for the perfect coat. Make it once and it will slide into your weekly rotation. If you try it, tell me how you served it and what veggies you added so we can swap ideas.