Pin it
Slow Cooker Mongolian Beef is the kind of dinner that makes the kitchen smell good long before you are ready to eat. The sauce is salty, sweet, garlicky, and thick enough to cling to every strip of beef.
The slow cooker does the heavy lifting, but this recipe still needs a little care. Slice the beef thinly across the grain, coat it lightly with cornstarch, and do not cook it all day if your cooker runs hot.
The Sweet Soy Lineup
The ingredient list is short, so use low-sodium soy sauce and fresh ginger if you can. Flank steak should be well chilled before slicing, which makes clean thin strips much easier.
- Flank steak. Slices into tender ribbons when cut thinly across the grain.
- Cornstarch. Lightly coats the beef and helps the sauce turn glossy as it cooks.
- Low-sodium soy sauce. Gives the dish its deep salty base without making the sauce harsh.
- Brown sugar. Balances the soy and helps the sauce cling to the beef.
- Hoisin sauce. Adds body, sweetness, and a little fermented depth.
- Garlic and ginger. Bring the sharp, warm flavor that keeps the sauce from tasting flat.
- Carrots. Add sweetness, color, and a little texture.
- Green onions and sesame seeds. Finish the dish with freshness and crunch.
Slow Cooker Mongolian Beef Method
- Slice the beef. Cut the flank steak across the grain into thin strips. Keep the slices about 1/4 inch thick so they soften without falling apart.
- Coat the strips. Toss the beef with cornstarch until lightly dusted. Shake off any heavy clumps before it goes into the cooker.
- Mix the sauce. Whisk soy sauce, water, brown sugar, hoisin, garlic, ginger, rice vinegar, sesame oil, and chili flakes in the slow cooker.
- Add beef and carrots. Stir in the coated beef and shredded carrots until everything is coated in sauce.
- Cook until tender. Cover and cook on low for 4-5 hours or on high for 2-3 hours. The beef should be tender and the sauce glossy.
- Finish and serve. Stir well, then top with green onions and sesame seeds. Serve over steamed rice or noodles.
Cut The Beef Thin
The biggest texture choice happens before the slow cooker turns on. Look at the flank steak and find the long muscle lines, then cut across them. If you slice with the grain, the pieces can taste chewy even after hours of cooking.
A cold steak is easier to handle. Put it in the freezer for 15 minutes if it feels floppy. You want thin strips, not paper-thin shavings. That size gives you tender beef that still holds its shape when stirred through the sauce.
Keep The Sauce Glossy
Cornstarch is doing more than thickening here. It catches on the surface of the beef, then mingles with the soy sauce and sugar as the meat releases juices. That is why the sauce becomes shiny instead of watery.
If your cooker runs cool and the sauce looks thin at the end, remove the lid and cook on high for 15-20 minutes. Stir once or twice. If it is still loose, whisk 1 teaspoon cornstarch with 1 tablespoon cold water and stir it in. Give it another 10 minutes. For safe cooking basics, the USDA safe temperature chart is a useful reference.
Add Vegetables Late
Carrots can cook from the beginning because they hold their shape and sweeten the sauce. Broccoli is different. Add it too early and it turns dull and soft.
For a full one-pot dinner, add broccoli florets during the last 25-30 minutes on high. Bell peppers need about the same time. Snow peas only need 10-15 minutes. If you like saucy beef with greens, try this same idea in slow cooker broccoli beef.
Make It Your Way
For more heat, double the chili flakes or add a spoonful of chili garlic sauce. For a deeper takeout flavor, add 1 extra tablespoon hoisin. If you need a gluten-free version, use tamari and a gluten-free hoisin sauce.
This recipe sits between sticky beef noodles and a rice bowl. For another cozy slow-cooker beef dinner, try slow-cooker sticky chilli beef noodles. When you want the same sweet-savory profile without the long cook, Mongolian ground beef noodles gets there fast.
Store And Reheat Gently
Leftovers keep well because the beef sits in plenty of sauce. Cool the dish, then refrigerate it in a covered container for up to 4 days. The sauce will thicken in the fridge.
Reheat with a splash of water in a small skillet over medium-low heat. Stir often and stop as soon as the beef is hot. The microwave works too, but use short bursts so the edges do not toughen.
Serve It With Rice
Steamed jasmine rice is the easiest base because it catches every spoonful of sauce. Brown rice, rice noodles, or cauliflower rice also work. Add sliced cucumbers or a simple cabbage slaw if you want something crisp next to the sweet sauce.
For a quick bowl night, spoon the beef over rice and add steamed broccoli. If you like beef bowls with a brighter garlic soy finish, quick easy Korean ground beef is a good next dinner.
Summary
This slow cooker beef is best served hot over rice with green onions, sesame seeds, and a crisp vegetable on the side.
FAQs
- What cut of beef is best for Slow Cooker Mongolian Beef?
Flank steak works well because it slices into long, tender strips and soaks up the sauce. Sirloin or skirt steak can also work. Slice any cut thinly across the grain so it does not feel stringy.
- Can I make this with stew meat?
You can, but the texture will be different. Stew meat needs a longer cook and will feel more like saucy pot roast than restaurant-style Mongolian beef strips. If using stew meat, cook on low until fork-tender.
- How do I make it less sweet?
Reduce the brown sugar to 1/4 cup and add an extra tablespoon of water or beef broth. The sauce will still glaze the beef, but it will taste more savory and soy-forward.
- Can I add broccoli to the slow cooker?
Yes, but add broccoli near the end so it stays green and tender-crisp. Stir in fresh florets during the last 25-30 minutes on high, or serve steamed broccoli on the side.
- How long does Mongolian beef last in the fridge?
Store leftovers in an airtight container for up to 4 days. Reheat gently in a skillet or microwave with a splash of water to loosen the sauce.
- Can I freeze Slow Cooker Mongolian Beef?
Yes. Cool it completely, then freeze in a sealed container for up to 2 months. Thaw overnight in the fridge and reheat gently so the sauce stays smooth.
