Slow Cooker Flank Steak cooks up ultra tender and juicy beef to perfection in the crockpot with a delicious garlic butter herb sauce in this easy recipe. This simple dump-and-go slow cooker dinner barely takes 10 minutes of prep time, and is a great weeknight dinner option. You’ll just need some pantry staples, your trusty slow cooker and a few minutes of kitchen time to get everything ready!

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If you always thought flank steak was a boring, bland, and underwhelming cut of meat, this recipe is going to change your mind. I used a simple mix of spices and other ingredients to cook the steak until it was beautifully tendera and then shredded it.
The shredded steak works perfectly as main dish for a hearty meal with mashed potatoes. And we love the leftovers as a filling for your tacos, quesadillas and fajitas with some creamy jalapeno sauce, smoked salsa, and Instant Pot queso. But that’s not all. There are actually a lot of other ways to serve it too!
Why You Will Love This Recipe
- Easy to make: You’ll need just 10 minutes of hands-on time to get all the prep work done, and after that, you just need to set it up and let the slow cooker work its magic. It’s the easiest way to cook flank steak there is.
- Foolproof: Cooking the steak in the slow cooker ensures that you have the perfect, juicy texture every single time.
- Customizable: You can also customize the mix-ins to your liking and tweak the flavors based on your personal preference!
- Perfect for holidays: The rich and melt-in-the-mouth meat served with the luxurious garlic sauce makes this dish perfect for the holidays or any special occasion when you’re entertaining.
Ingredients

- Flank steak: Flank steak is one of the most versatile cuts of beef and it's affordable too! Pick one that has a uniform thickness, so that it is cooked to perfection. If you don’t have flank steak, skirt steak is your next best bet.
- Seasonings: To season, I used a mix of garlic powder, onion powder, Italian seasoning blend, some salt and pepper.
- Aromatics: I also used fresh onion and garlic to add some savory depth to the au jus as well as add some moisture to the pot.
- Butter and olive oil: The butter cooks with the steak giving it richness and to keep the steak nice and moist while the olive oil works to sear the flank steak.
- Beef broth and au jus packet: To cook the steak in and keep it from drying out while the au jus is a convenient way to add more flavor. Use low sodium beef broth if you’re concerned about the high sodium content.
See the recipe card below for exact ingredient amounts, nutritional information, and detailed instructions.
Variations
- Add some spice: To bring a kick of heat to the crockpot steak, add some red pepper flakes or cayenne pepper into the mix.
- Extra flavor: To add some extra flavor to the au jus, you can also add a dash of Worcestershire sauce or a mix of soy sauce and some brown sugar into the crockpot along with the other ingredients.
How to Make Flank Steak in the Slow Cooker
To make the flank steak in a slow cooker, start by greasing it with some cooking spray.

Step 1: Season the steak. Sprinkle the steak with salt, pepper, garlic and onion powder and Italian seasoning and rub it into both sides of the steak.

Step 2: Sear the steak. Heat the oil in a large skillet and sear the steak on both sides on high heat until the surface is golden brown.

Step 3: Soften the onions and garlic. Microwave the onions and garlic for a few minutes until they’re slightly soft.

Step 4: Prepare the au jus mixture. Add the packaged au jus and beef broth to a small bowl and mix it well.

Step 5: Arrange. Place the steak in the slow cooker and distribute the onions and garlic evenly around it. Pour the au jus mixture evenly on top of everything.

Step 6: Top with butter. Place the butter on the top of the steak.

Step 7: Cook. Cover and cook the steak on low for 6-8 hours or on high for 3-4 hours.

Step 8: Remove and shred. When the steak is ready, shred it with two forks or slice it thinly. Serve and enjoy!

Recipe Tips
- Add veggies: You can bulk up the dish by adding some veggies like potatoes, carrots, and mushrooms to the slow cooker halfway through the cooking time.
- Slice right: Slice the steak against the grain to keep it from getting chewy. Doing this shortens the fibers and gives you that perfect tender and juicy meat in every bite.
- No salt: This dish is on the salty side. If you want to lower the salt content omit the additional salt on the meat when searing.
If you love flank steak recipes like this one, you may also enjoy my Smoked Flank Steak.
Storage Directions
- Storing: You can store your leftover crockpot flank steak in the refrigerator for 2-3 days. Make sure you use an airtight container to keep it fresh.
- Reheating: You can reheat it in the microwave, pausing every 30 seconds to give it a quick stir. Another great way is to reheat it in a pan over low heat, stirring continuously until it is nice and warm.
- Freezing: You can also freeze the leftovers if you want to. Just allow them to cool down completely and transfer them to a freezer-safe container or bag. You can freeze them for 2-3 months. You will want to thaw them overnight in the refrigerator before reheating.

Serving Suggestions
- There are lots of ways to serve this slow cooker beef flank steak. I particularly love serving the shredded flank steak with some classic mashed potatoes and a green bean dish like sweet green beans or balsamic green beans.
- On days when I want to make the dish a bit fancier, I swap the mashed potatoes with my mashed potato patties or this mashed potato casserole. You can also team it up with some air fryer dinner rolls if you want to keep it simple.
- It also turns out to be an amazing filling for your homemade sandwiches, which you can serve with some air fried steak fries on the side.
Recipe FAQs
Browning the steak adds a beautiful depth of flavor to it. In my opinion, it’s an absolute must, and those few extra minutes are totally worth it.
If the sauce seems too thin, add a slurry made using cornflour and water towards the end, let it simmer for a minute while stirring and it’ll thicken up nicely.

Video
More Delicious Slow Cooker Recipes
Do you need more crockpot dinner ideas? Here are some recipes you may also like to try.
If you try this recipe and love it please leave a star rating in the recipe card below or even better, drop a review in the comment section, I always appreciate your feedback. Be sure to follow along with me on Facebook, Pinterest, and YouTube for more easy recipes!

Slow Cooker Flank Steak
Equipment
- Slow Cooker 8 quart
Ingredients
- 1 2 pound flank steak
- 1 teaspoon garlic powder
- 1 teaspoon onion powder
- 1 teaspoon Italian seasoning blend
- ½ teaspoon salt
- ½ teaspoon pepper
- 2 tablespoons extra virgin olive oil
- 1 cup thinly sliced onion
- 3 cloves garlic
- 1 package au jus mix
- 1 cup beef broth
- ¼ cup unsalted butter
Optional
- fresh parsley
Instructions
- Prepare a 8 quart slow cooker with cooking spray.
- Season the flank steak with garlic powder, onion powder, Italian seasoning, salt and pepper.
- Heat oil in a large skillet over high heat and sear the seasoned flank steak on both sides.
- Place the steak in the prepared slow cooker.
- In a small bowl, soften the garlic and onions in the microwave for about 3 minutes then distribute them evenly around the flank steak.
- In a second small bowl, whisk together the au jus mix and beef broth until well combined and pour over the steak, garlic and onions.
- Place the butter on top of the steak.
- Cover and cook on low for 6-8 hours or high for 3-4 hours.
- Remove from the slow cooker and shred or slice. (The meat is more likely to shred as it will be super tender from cooking low and slow.)
- Top with optional fresh parsley and serve.
Notes
- Feel free to add some veggies like potatoes, carrots, and mushrooms to the slow cooker halfway through the cooking time.
- If slicing rather than shredding, slice the steak against the grain to keep it from getting chewy. Doing this shortens the fibers and gives you that perfect tender and juicy meat in every bite.
- This dish is on the salty side. If you want to lower the salt content, you can omit the additional salt on the meat when searing.
Nutrition
This post was originally published in March 2018. It's been updated with new content, revised recipe, and images.
Starla says
I’m so glad I tried this recipe. We all loved it and can’t wait to make it again. So tender. I still can’t believe how well this steak cooked in my slow cooker. Will definitely make again. So good. Thx
Karin and Ken says
I’m so glad you tried it too. It’s so easy and so tasty. Thank you for taking time to let me know. I’m always happy to hear when others enjoy my food! All the best. Karin
Carla says
Fantastic. Beyond my expectations. Will definitely make again. Everyone loved it. So beautifully tender. This recipe is a hit. Thank you for sharing this flavorful easy recipe.
Karin and Ken says
This recipe is a hit in our house too! So glad you enjoyed it. You just made my day. All the best. Karin
Colleen says
Exceptional flavor and I think it’s the best flank steak I’ve ever had. I didn’t think it was possible in a slow cooker but was I wrong. This recipe is a definite keeper. Thank you for another great recipe. Love your site!
Karin and Ken says
I’m so happy to hear you enjoyed this recipe as much as we do! Hopefully you find some other recipes on this site that you enjoy just as much. All the best. Karin