Crockpot Beef Lo Mein

One of my favorite mom hacks for busy nights is to throw a takeout-inspired dinner into the crockpot. It’s way cheaper than ordering in, it requires just a little bit of prep earlier in the day, and it’s a meal that I know everyone’s going to eat!

This crockpot beef lo mein is one of those recipes, and it always gives me serious feel good vibes. Tender slices of beef simmer in a savory, slightly sweet sauce with garlic and ginger, then get tossed with noodles and crisp-tender vegetables at the end. It’s cozy, filling, and feels like takeout, but you barely have to think about it!

While you’re here, I think you’ll also love my crockpot chicken curry, crockpot egg roll in a bowl, crockpot pork lo mein, crockpot taco casserole, and crockpot Mexican pulled pork!

Ingredients

Please note: I always include a printable recipe card at the bottom of the post! I recommend that you don’t skip the coming sections though, where I’m sharing hints, tips, and ideas to help you create the best results! 

• Flank steak: Thinly slicing against the grain keeps the beef tender after slow cooking. Flank works especially well because it absorbs the sauce beautifully.

• Oil: Used for quickly searing the beef to build flavor before it goes into the crockpot.

• Onion: Adds natural sweetness and depth as it cooks down into the sauce.

• Beef broth: Forms the base of the sauce and keeps everything from becoming too salty from the soy sauce.

• Soy sauce: Brings that classic lo mein savory flavor. You can use low-sodium if preferred.

• Brown sugar: Balances the saltiness and adds a subtle sweetness to the sauce.

• Ground ginger: Adds warmth and that familiar takeout-style flavor. Fresh ginger works too if you have it.

• Black pepper: Adds gentle heat without making the dish spicy.

• Garlic: Essential for depth and aroma.

• Shredded carrots: Add color, sweetness, and texture.

• Bell peppers: Bring freshness and a slight crunch.

• Broccoli florets: Stirred in later so they stay tender-crisp.

• Snow peas: Add brightness and that classic lo mein texture.

• Lo mein noodles, udon, or fettuccine: The base that soaks up the sauce. Lo mein is traditional, but the swaps work well in a pinch.

• Cornstarch: Thickens the sauce at the end so it coats the noodles properly.

• Scallions & sesame seeds: Optional, but they add freshness and that finished, takeout-style look.

How To Make Crockpot Beef Lo Mein 

• Heat the oil in a skillet and quickly sear the beef slices just until browned. They don’t need to cook all the way through—just get some color.

• Transfer the beef to the slow cooker.

• Add the onion, broth, soy sauce, brown sugar, ginger, pepper, garlic, carrots, and bell peppers.

• Cover and cook on LOW for 4–5 hours, until the beef is tender.

• Stir in the broccoli and snow peas.

• In a small bowl, mix the cornstarch with ½ tablespoon cold water to create a slurry, then stir it into the slow cooker.

• Add the cooked noodles and gently toss everything together until well coated in the sauce.

• Let it heat through for 15–20 minutes before serving.

Storage & Reheating 

Store leftovers in an airtight container in the refrigerator for up to 3 days. Reheat gently with a splash of broth to loosen the noodles.

Recipe Notes 

Slice the beef thinly against the grain to keep it tender after slow cooking. Add the vegetables near the end so they stay crisp-tender instead of turning mushy. This is super important when slow cooking – ask me how I know! When stirring in the noodles, toss gently so they don’t break apart. If you can’t find lo mein noodles, fettuccine or udon noodles both work well as substitutes.

Variations

You can easily switch this crockpot beef lo mein up depending on what you have in your kitchen. I always try to give extra ideas for variations so you don’t have to rush out to the store! Add baby corn or water chestnuts for extra crunch and texture. If you like a little heat, stir in some chili paste or sriracha to taste (this is my favorite tweak!). You can also swap the beef for chicken or even shrimp if you want to change things up.

Serving Ideas

This crockpot beef lo mein is hearty enough to stand on its own, but you can easily round it out with a few simple sides. Serve it with egg rolls, dumplings, or a quick cucumber salad for that full takeout-at-home feel. It also pairs well with steamed edamame or a light stir-fried vegetable on the side if you want to add a little extra color to the table.

Troubleshooting 

• My noodles are mushy: This usually happens if they sit too long in the slow cooker. Add them at the end and only heat through for 15–20 minutes.

• The sauce is too thin: Let it cook uncovered for a bit longer after adding the cornstarch, or stir in a small additional slurry if needed.

• The sauce is too salty: Try adding a splash of beef broth or a small squeeze of lime to balance it out. Low-sodium soy sauce also helps next time.

• The beef seems tough: Make sure it’s sliced thinly against the grain. Thicker slices can stay chewy even after slow cooking.

• The vegetables are too soft: Add them later in the cooking process so they stay crisp-tender.

Print Recipe

5 from 1 vote

Crockpot Beef Lo Mein

This crockpot beef lo mein is a simple, takeout-inspired dinner made with tender beef, colorful vegetables, and noodles tossed in a savory sauce. It’s an easy slow cooker meal that’s perfect for busy weeknights and just as satisfying as your favorite takeout.

Prep Time20 minutes mins

Cook Time4 hours hrs

Total Time4 hours hrs 20 minutes mins

Course: Main Course

Servings: 6

Ingredients

• 1½ pounds flank steak thinly sliced against the grain
• 1 tablespoon oil
• 1 small onion thinly sliced
• 2 cups beef broth
• ½ cup soy sauce
• ¼ cup brown sugar
• 1 teaspoon ground ginger
• 1 teaspoon black pepper
• 3 cloves garlic minced
• 1 cup shredded carrots
• 1 cup sliced bell peppers
• 1 cup broccoli florets
• 1 cup snow peas
• 12 ounces lo mein noodles or udon noodles or fettuccine, cooked and drained
• ½ tablespoon cornstarch
• Scallions and sesame seeds for garnish

Instructions

• Heat the oil in a skillet and quickly sear the beef slices just until browned. They don’t need to cook all the way through—just get some color.
• Transfer the beef to the slow cooker.
• Add the onion, broth, soy sauce, brown sugar, ginger, pepper, garlic, carrots, and bell peppers.
• Cover and cook on LOW for 4–5 hours, until the beef is tender.
• Stir in the broccoli and snow peas.
• In a small bowl, mix the cornstarch with ½ tablespoon cold water to create a slurry, then stir it into the slow cooker.
• Add the cooked noodles and gently toss everything together until well coated in the sauce.
• Let it heat through for 15–20 minutes before serving.

These crockpot noodles are a total lifesaver on those days when you want a family friendly meal and are trying to resist the urge to just order takeout! If you’ve tried them, let me know how they turned out for you. You can leave a comment and a star rating below, and tag me in your pics on Instagram @slimmingviolet and #slimmingviolet. Enjoy!