Slow Cooker Flank Steak

I love making slow cooker flank steak for a simple, no-fuss way to enjoy a lean cut of beef. My recipe is foolproof, cooks to perfection every time, and my family loves it!

My Easy Flank Steak Crock Pot Recipe

I first got the idea for my slow cooker flank steak when I had a packed day ahead of me but wanted to be able to enjoy a wonderful dinner with my family once we got home. I had some flank steak in the fridge and decided to try cooking it in the Crock Pot.

Marinating is the key to tenderizing flank steak. I didn’t have time to marinate it overnight, so I decided to see what would happen if I let the steak marinate as it cooked in the slow cooker. I threw in a few ingredients, coated the steak, and let the Crock Pot work its magic.

When we came home that evening and pulled out the steak, I could tell right away that it was perfectly tender. We sat down and tried a bite, and I knew from the reaction on my husband Ben’s face that this recipe was our new favorite set-it-and-forget-it meal, and I was right.

He looked at me and told me, “This is dangerously good.” Mission find a new easy dinner recipe that tastes amazing was a success!

And, if you love flank steak recipes, try my recipes for steak fajitas, slow cooker flank steak, instant pot flank steak, air fryer flank steak, my easy steak marinade, and of course, my other steak recipes like London broil and sirloin tip.

Flank Steak Recipe in the Slow cooker Ingredients

• Flank steak
• Balsamic vinegar
• Oil – I use olive oil, but vegetable oil or canola oil work as well
• Honey – I’ve also used maple syrup instead
• Worcestershire sauce
• Dijon mustard
• Garlic
• Salt and pepper

How to Make Slow Cooker Flank Steak

A full printable version of this recipe with ingredient measurements is available at the bottom of this post.

STEP ONE: Mix the balsamic vinegar, oil, honey, Worcestershire sauce, Dijon mustard, garlic, salt, and pepper in a small bowl.

STEP TWO: Place the marinade and flank steak into the slow cooker. Coat the steak with the marinade and flip it once before cooking.

STEP THREE: Cook the steak for about 6 hours on the low setting or 3-4 hours on high until the meat becomes very tender.

STEP FOUR: Once cooked, carefully move the steak to a cutting board. Let it rest for 5-10 minutes, then slice it against the grain into strips and serve.

Tips and tricks for Cooking Flank Steak in the Slow Cooker

• Look for uniform thickness in the flank steak to ensure the most even cooking.
• Cook it on low for 6 hours to get the most tender steak. I’ve cooked it on high for 3-4 hours, and it’s still tasty, but the low-and-slow method gets the steak so tender!
• Flip the steak in the marinade in the slow cooker once or twice. I always try to make sure the steak is fully coated in marinade for maximum flavor.
• Do not add water to the slow cooker. I know it can be tempting to add it to help the steak cook, but the steak will cook perfectly just in the marinade.
• Let the steak rest for a few minutes before slicing to help it retain all its juices. I also slice it against the grain for super tender bites.

Flank Steak Crock Pot Variations and substitutions

• Add fresh herbs to the marinade. I’ve used full sprigs of rosemary or thyme when marinating the steak overnight, so they’re easy to pull out before adding the steak and marinade to the slow cooker.
• Switch up the marinade to try a whole different flavor. I love a sweet and savory teriyaki, zesty chimichurri, or refreshing herb and lemon blend. Spices like chili powder, paprika, and brown sugar also make a nice spice rub.
• Put potatoes, peppers, and/or onions around the outside of the steak in the slow cooker halfway through the cooking time to bring some flavor to the veggies.
• Play around with the acidity. I usually use balsamic vinegar, but red wine vinegar or apple cider vinegar are great for adding unique flavor that still tenderizes the steak.
• Add some heat by sprinkling crushed red pepper flakes in the slow cooker.
• Use the flank steak or even its leftovers as the star of foods like tacos, fajitas, or even quesadillas. I just use tortillas, steak, guacamole, and some sour cream!

What to Serve With Flank Steak Recipes in the Slow Cooker

For a simple side that complements the steak beautifully, I usually make easy biscuits and vegetables like air fryer carrots, or air fryer sweet potato cubes.

I also love serving slow cooker flank steak with mashed potatoes without milk and then pouring mushroom gravy over the whole plate. Rice also works great for this too!

Slow Cooker Flank Steak FAQs

How can I keep my crock pot flank steak from getting chewy?

Unlike most cooking methods where chewy steak means it’s overcooked, a chewy slow-cooked steak actually means it’s undercooked. I always make sure to give the steak a full 6 hours on low and sometimes even up to 8 hours depending on the size!

I also recommend cutting the flank steak against the grain, which shortens the fibers and makes the steak easier to chew.

What’s the difference between flank steak and skirt steak?

While both are flavorful cuts, skirt steak is thinner, which makes it cook more quickly. I prefer flank steak for the Crock Pot because it’s thicker, so it benefits from cooking low and slow, but this is my favorite way to make skirt steak in the slow cooker. 

How can I store slow cooker flank steak?

I let my flank steak fully cool before storing it in an airtight container in the refrigerator. I recommend enjoying leftovers within 3-4 days.

To reheat, I like to warm the steak slowly in a pan on the stove with a splash of liquid. If I’m in a rush and need to microwave it, I’ll use 50% power and heat the steak in 30-second bursts until warmed through.

More Easy Slow Cooker Dinner Recipes

• Slow cooker pulled pork
• Velveeta mac n cheese in the crock pot
• London broil slow cooker recipe
• Chicken with stuffing in the crock pot
• Slow cooker ranch pork chops
• Mississippi chicken
• BBQ meatballs in the crock pot