Slow Cooker Mongolian Beef

Something about the scent of slow cooker Mongolian beef drifting through the house just does things to your imagination… I remember standing in the hallway once, coat halfway on, completely forgetting where I was headed because it smelled so good. It’s rich and a bit sweet, with those caramelized notes from seared beef tangled in garlicky, gingery sauce that clings to your spoon – not fancy, just soul-hugging. And the tenderness? You barely need to chew. It’s the kind of dinner that somehow tastes like you tried really, really hard, but secretly didn’t.

Why You’ll Crave It

• No last-minute flurry – you set it up, it takes care of itself, and hours later: magic.
• The sauce is this glossy, sticky, deeply flavored thing you’ll want to mop up with rice. Or bread. Or frankly, anything.
• You can leave it plain or add veggies at the end – it’s forgiving.
• Leftovers are bizarrely even better – richer, deeper, more… somehow.
• It’s lovely for gatherings, but also just right for a solo Sunday supper with slippers on.

The first time I made this, my brother showed up unexpected and ate three full servings standing up – straight from the pot.

What You’ll Need

• 1 ½ pounds flank steak: sliced thin against the grain – this matters for tenderness
• ¼ cup soy sauce: I like low-sodium so it doesn’t overpower everything
• ¼ cup brown sugar: light or dark, depending on the depth of sweetness you want
• 2 cloves garlic: minced, not smashed, you want those tiny pieces to melt in
• 1 teaspoon fresh ginger: finely grated – bright and a little spicy
• ½ cup beef broth: not too salty, just enough to loosen the sauce a bit
• 1 tablespoon cornstarch: used early to coat the beef, helps with the thickening later down the line
• 2 tablespoons vegetable oil: for searing, high smoke point needed here
• 3 green onions: sliced on the bias for garnish (and a gentle pop of color)
• Cooked rice: for serving – plain white jasmine works beautifully

Easy How-To

Slice and Dust the Beef

If you’ve got flank steak, trim off any obvious excess fat and slice it thin – really thin – across the grain. Toss it gently with the cornstarch and let it sit. This little moment helps give it that signature silky-soft texture in the end.

Stir the Sauce Together

In a bowl, maybe the one with a pour spout if you have it, whisk together the soy sauce, brown sugar, ginger, garlic, and beef broth until it loses that gritty sugar feel. Don’t rush it.

Quick Sear (Don’t Skip)

Heat up the oil in a wide pan – not too hot, not smoking, just shimmering. Sear the beef slices in batches so they brown and don’t steam. Each piece needs a little space. It’s a nice ritual, and it goes faster than you think.

Assemble in the Slow Cooker

Layer the seared beef in your slow cooker, then pour the sauce over. Give it a gentle stir so everybody’s tucked in down there. Lid goes on now.

Let It Do Its Thing

Low for about 6 hours or high for 3 – depending on the kind of day you’re having, or how soon you want your kitchen to smell like dinner already happened.

Thicken It Up (Optional but lovely)

If you like a clingy sauce, mix up another teaspoon of cornstarch with some cold water and stir that slurry in maybe 30 minutes before you’re ready to serve. The sauce will shine a little more and coat everything better.

Garnish and Serve

Spoon over warm rice, shower it with green onions, and then pause – even just for two seconds – to appreciate the steam rising up and what you just created.

Good to Know

• Don’t be afraid of the sugar – it balances out the salt and ginger in a way that’s oddly addictive.
• If your meat turns out dry, it likely cooked too long or sliced too thick – but honestly even then, the sauce somehow saves it.
• I once added a splash of rice vinegar out of curiosity… it didn’t ruin anything, but it definitely wasn’t the same cozy dish.

Serving Ideas

• Spoon it over steamed white rice, sure, but don’t ignore soba noodles or even mashed sweet potatoes for a softer play on sweet and savory.

Top Tricks

• If you pop the steak in the freezer for 10-15 minutes before slicing, it’s much easier to cut those tidy, thin strips.

Frequently Asked Questions

Can I cheat and skip searing the beef?

Technically yes… but the rich depth of flavor from that golden-brown crust adds something lovely. If you have even 10 minutes, it’s worth doing.

Can I make this ahead of time?

Absolutely. It keeps well in the fridge and somehow deepens in flavor overnight. I often reheat it gently on the stove with a splash of water to loosen things up.

What if I don’t have a slow cooker?

A Dutch oven will work too – just simmer very low on the stovetop or in a low oven. Keep an eye out so it doesn’t dry out without that sealed lid effect from the slow cooker.

Is this dish freezer-friendly?

Yes, once it’s cooled. I like to pack individual portions with rice – makes a surprisingly comforting desk lunch later on.