Ultimate Slow Cooker Mongolian Beef

The first time my coworker brought this to a potluck, I stood by the slow cooker for twenty minutes waiting for the serving spoon to free up. Something about that sauce—sweet and salty and clinging to every bite of beef—had everyone hovering around the kitchen island.

My sister-in-law now makes this every Sunday during football season. Her house has become the unofficial gathering spot, and I swear the neighbors can smell the hoisin and garlic from three doors down.

Ingredients

• Flank steak: Thinly slice against the grain yourself rather than asking the butcher—it stays more tender that way
• Low-sodium soy sauce: Regular soy sauce makes this way too salty since the sauce reduces down in the slow cooker
• Brown sugar: Dark brown sugar gives you that gorgeous molasses depth and deeper color
• Hoisin sauce: This is the secret ingredient that makes it taste restaurant-quality not just homemade beef
• Fresh garlic: Jarred minced garlic works in a pinch but fresh gives you that aromatic punch that fills the whole house

Instructions

Get your slow cooker ready:

A quick spray of nonstick spray makes cleanup so much easier later

Prep the beef:

Lay your flank steak on the cutting board and slice it thin going across the grain—the meat should almost shred apart when you pull it

Whisk the sauce:

Combine soy sauce brown sugar hoisin and garlic in a bowl until the sugar dissolves into a smooth glossy mixture

Combine everything:

Pour that gorgeous sauce over the beef and toss it around until every piece is coated

Let it cook:

Cover and cook on low for 4 hours until the beef is fall-apart tender and the sauce has thickened into something incredible

Final stir and serve:

Give it a good stir before serving over hot steamed rice with some broccoli on the side

Save

Last winter my friend texted me at 9pm that her family had declared this their new favorite dinner. Her kids asked for it three nights in a row.

Making It Thicker

Sometimes you want that sauce to really cling to the rice. Mix two tablespoons of cornstarch with two tablespoons of cold water until smooth and stir it in during the last thirty minutes of cooking.

Customizing the Heat

My husband likes to add red pepper flakes right at the start so the heat builds slowly. I prefer sprinkling them on at the end so I can control how spicy each bowl gets.

Serving Suggestions

Jasmine rice soaks up that sauce perfectly but cauliflower rice works great if you are watching your carbs.

• Sliced green onions add the perfect fresh crunch and pop of color
• Sautéed broccoli or snow peas round out the meal beautifully
• Extra sauce on the side is never a bad idea

Save

This is the recipe that convinced my slow-cooker-skeptic husband that sometimes the easiest method makes the best meals.

Recipe FAQs

→ Can I use a different cut of beef?

Yes, you can use sirloin or round steak, but flank steak works best as it becomes tender when sliced against the grain. If using other cuts, you may need to adjust cooking time slightly.

→ How do I make the sauce thicker?

Dissolve 2 tablespoons cornstarch in 2 tablespoons cold water and stir into the slow cooker during the last 30 minutes of cooking. This will create a thicker, more cohesive sauce.

→ Is this gluten-free?

Yes, simply use tamari or gluten-free soy sauce and ensure your hoisin sauce is gluten-free. The dish maintains all its flavor while being suitable for gluten-sensitive diets.

→ What's the best way to serve this?

Serve hot over steamed jasmine rice or with sautéed broccoli. The rich sauce pairs perfectly with these sides and makes for a complete, satisfying meal.

→ Can I make this ahead of time?

Absolutely! The flavors actually improve when made ahead. You can refrigerate and reheat gently on the stovetop or in the microwave before serving.