Sous Vide Flank Steak With Creamy Peppercorn Sauce

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This sous vide flank steak is tender, succulent, juicy and just perfection served with a creamy peppercorn sauce. Cooking the flank steak using the sous vide method results in perfectly tender, medium rare meat every time!

That's the great things about sous vide cooking. You can take a cut of meat that can tends to be a touch tough (like flank steak or this sous vide lamb), and cook it to a melt-in-your-mouth perfection without it ever being over or under- done.

But even tender meats, like this sous vide filet mignon, are perfect in the sous vide! Plus you can cook your steak from frozen which is super convenient.

And if you're a lover of flank steak (this grilled flank steak is incredible too), I really believe sous vide is an amazing way to go. Cooking it slowly at a steady temperature in a water bath gives all the connective tissue just enough time to start breaking down and tenderizing the meat.

A quick blazing hot sear on either side once it's done results in meat-eating perfection - like we do for this sous vide ribeye, sous vide porterhouse, sous vide sirloin, sous vide tri tip, sous vide picanha, and these sous vide veal chops also.

And the peppercorn sauce is the perfect accompaniment to this sous vide flank steak. However, if peppercorns aren't your thing, this chimichurri sauce is just incredible as well.

Check out this sous vide steak guide!

Jump to:

• What is Sous Vide?
• Ingredients
• Step By Step Instructions
• Expert Tips
• Recipe
• 💬 Comments

What is Sous Vide?

Sous vide is the process of vacuum sealing your food and cooking it in a temperature controlled water bath. Cooking it this way makes it almost impossible to overcook anything you're cooking.

You can create food exactly how you want it done every time. Restaurants have been using it for a long time, and companies have now started to introduce home cook versions.

I use the Sous Vide Anova Precision Cooker and have been incredibly happy with it.

What is the Water Displacement Method?

The displacement method is where you slowly submerge a ziplock bag in water pushing the air out of the top of the bag (the bag should be slightly open at the top to allow air to escape).

Use a clip (I use sous vide magnets) to clip the bag to the side to keep it from floating and getting air and/or water inside.

Tools Used

• Anova Precision Sous Vide Cooker
• 12 quart container
• Vacuum sealer
• Vacuum-seal bags

You will also want to check out these posts on the best sous vide containers and the best sous vide bags for more information!

If you don't have a lot of experience cooking sous vide yet, you may want to pop over and read what sous vide cooking is and the benefits of sous vide cooking.

Ingredients

The full list of ingredients and amounts is included in the recipe card at the bottom of the post.

Flank steak can be found in the meat department at your local grocery store. Flank steak is a cut of beef that is taken from the abdomen of the cow. It needs to be marinated or slow cooked to allow the fibers to break down and become tender.

Flank steak is actually one of my favorite cuts of beef as it has such a wonderful flavor. One of my favorite ways to cook it (besides using sous vide) is actually marinating it in this chicken marinade overnight, then grilling it.

I highly recommend using fresh whole peppercorns and using a mortar and pestle to crack them for the sauce. Tellicherry peppercorns has the best flavor for this and I use them all the time!

Step By Step Instructions

Clip the immersion circulator to the side of a large container (I prefer to use this sous vide container) and heat to 129F degrees.

Pat the flank steak dry and season on both sides with half the salt and pepper.

Place in a plastic bag and vacuum seal (I like to use a Foodsaver for the best results). You can also use a ziplock bag and slowly drop it in the water while sealing to get it airtight (this is called the water displacement method explained above).

**Make sure the beef is flat in the plastic bag to ensure it cooks properly. 

Once the water is heated to the correct temperature, place the bag in the water. It should sink to the bottom, but if it floats, clip the bag to the side to ensure the meat stays fully submerged in the water.

Cook for 2 hours.

Remove from the water and plunge the bag into an ice bath for 10 minutes. The ice bath brings the temperature down so the beef doesn't overcook when you sear it.

Remove the beef from the bag and pat dry with paper towels. Season again with the remaining salt and pepper.

Heat a skillet over high heat and add a high smoke point oil (ghee is my favorite, but you can use vegetable oil, avocado oil or coconut oil).

Add the meat and sear for 2 minutes per side, until a brown crust has formed on each side.

**You can also use a grill to sear the meat

Remove from the skillet and let it rest for 10 minutes. Slice it against the grain and serve it with the peppercorn sauce (below).

How to Make Peppercorn Sauce

While the steak rests, reheat the skillet you used to cook the beef on medium heat. Add the brandy to de-glaze and cook for 1 minute (until the alcohol has burned off).

Add the crushed peppercorns, salt and beef broth and bring to a simmer.

Stir in the cream and simmer for about 3-4 minutes to thicken, until the sauce coats the back of a spoon. Add additional salt to taste if necessary.

What to Serve with Flank Steak

I am a HUGE fan of serving this flank steak with these truffle mashed potatoes. It's one of my favorite sides.

You can also do steak frites and serve it with these truffle fries. Try some of these other favorites as well:

• Crispy Roasted Potatoes
• Instant Pot Broccoli
• Creamed Pearl Onions
• Honey Balsamic Brussels Sprouts
• Crispy Smashed Potatoes

This steak is also great leftover. Because the sous vide makes it so tender, it actually works wonderfully in this steak sandwich, or sliced, warmed in a skillet, and served on tortillas as tacos.

And you can also make this flank steak alongside these sous vide scallops if you'd like a little surf and turf - and you definitely want to follow it up with this sous vide crème brulee!

Expert Tips

1. The beef needs to be flat in the bag to cook properly on all sides.
2. Make sure the plastic bag is airtight for cooking.
3. When searing, make sure the skillet (or grill) is searing hot - it should be smoking - before adding the beef. This enables a nice crust to form without over cooking the meat.
4. The steak can also be seared on the grill instead of a skillet.
5. If you're not going to sear the steak immediately upon removing from the sous vide, plunge the bag in ice water to cool it and store it in the fridge or freezer.

Can You Sous Vide Frozen Flank Steak?

Absolutely! This is another ultra convenient thing about sous vide cooking - many times you can cook meat or seafood straight from frozen. Just add an hour to the cook time (3 hours total).

Did you make this sous vide flank steak? Rate the recipe and leave a comment to let me know how you liked it!

Recipe