You can’t beat sous vide! It’s one of my favorite hands-off cooking techniques because it cooks everything, from sous vide eggs to sous vide pork tenderloin to sous vide salmon, to perfection while sealing in the natural flavors. This sous vide flank steak recipe is no different, transforming this naturally tough steak into a perfectly marinated and succulent masterpiece. Finished in a hot skillet for a gorgeous seared crust, every bite is irresistible!
Why sous vide flank steak?
I’m proud to say that I’ve mastered sous vide steak. It’s one of the most reliable ways to cook steak because it seals in the natural juices and cooks the steak at a consistent, precise temperature. All you have to do is sit back and wait for it to finish! Not convinced yet? Just check out these other reasons why this I LOVE this recipe:
Tenderization. The low and slow cooking helps tenderize and preserve the natural juices in the meat. This is perfect for tougher cuts, like flank steak! Consistent results. Say goodbye to dry, overcooked meat. Unlike pan-seared steak or classic grilled flank steak, the water bath is temperature-controlled to help consistently cook your steak to the exact doneness you desire. Customize the flavor. Flank steak was meant to be marinated, so go ahead and load the sous vide bag with different seasoning blends, herbs, and aromatics to personalize the flavor profile. Just plain convenient. I kept this recipe mostly hands-off to make your next taco Tuesday or steak night as stress-free as possible.
Ingredients needed
Besides the steak, you also need a handful of ingredients to infuse the meat with balanced flavors. Here’s what you’ll need:
Flank steak. Also called bavette steak, flank steak is one of the best steaks to sous vide! I recommend picking up a well-marbled cut that’s about 1 to 1 ½ inches thick. If it’s too thick or uneven, you can pound the meat with a meat mallet for a uniform thickness. Balsamic vinegar. It gives the marinade a complex, sweet-tangy flavor and helps tenderize the meat. Dijon mustard. Just enough for a tangy and complex flavor. Salt and black pepper. To taste. Garlic powder. I used garlic powder out of convenience, but feel free to substitute a couple of fresh garlic cloves. Chili flakes. For a subtle kick of heat. Butter. After the sous vide, you’ll finish the steak in a sizzling cast iron skillet with butter to give it a nice crust around the outside.
How to sous vide flank steak
I’ve included step-by-step photos below to make this recipe easy to follow at home. For the full printable recipe instructions and ingredient quantities, scroll to the recipe card at the bottom of this post. Step 1 – Prepare the sous vide bag. Stir the salt, black pepper, garlic, chili, balsamic vinegar, and Dijon mustard in a bowl. Place the steak in the sous vide bag and pour the mixture over the steak. Vacuum seal the bag. Step 2 – Sous vide the flank steak. Fully submerge the bag in the water bath and cook to your desired doneness. Remove from the water bath and discard the marinade. Step 3 – Sear, rest, and slice. Heat the butter in a heavy-bottomed skillet, then sear the steak on both sides. Let it rest before slicing and serving.
Recipe tips and variations
Use a vacuum sealer. The seal on the bag needs to be watertight with no air pockets. Use a vacuum sealer or the water displacement method to seal it super tight. Pat dry before searing. Dry the steak with paper towels before the final searing step. Any excess moisture can prevent the crust from developing. Don’t skip the sear. Steakhouse-quality steak needs a crispy golden crust around the outside, so don’t skip the final sear if you want those results! For the perfect sear, make sure your skillet is smoking hot so each side of the steak crisps in about a minute or so. Rest before slicing. Place the flank steak on a cutting board to rest for about 10 minutes after searing. This makes the meat extra moist and flavorful. Customize the flavor! You can marinate flank steak before you pop it in the sous vide bag or pour the liquid right into the bag. Experiment with different sauces, like teriyaki, 3-ingredient steak marinade, bulgogi sauce, or stir fry sauce.
Storage instructions
To store: Store the cooled leftover flank steak in an airtight container or sealed plastic bag and refrigerate for up to 3 or 4 days. Use these cooking temperatures and times as a guide to sous vide the steak to your desired doneness:
Rare: Cook at 125°F (51.7°C) for 2 to 4 hours. Medium-Rare: Cook at 130°F (54.4°C) for 2 to 4 hours. Medium: Cook at 140°F (60°C) for 2 to 4 hours. Medium-Well: Cook at 150°F (65.6°C) for 2 to 4 hours. Well-Done: Cook at 160°F (71.1°C) for 2 to 4 hours.
Remember that these cooking times and temperatures will vary depending on the thickness of your steak and how you like it cooked. My family prefers a slightly firm texture, so I sous vide for about 2 hours. For a more soft and tender texture, aim for 4 hours. To freeze: The leftover steak also freezes well for about 2 to 3 months. Thaw it overnight in the fridge before reheating. To reheat: Place the steak in a baking dish and reheat in the oven at 325°F until it’s warmed through. Alternatively, warm the slices in a skillet over medium heat.
Frequently asked questions
More flank steak recipes
Beef Negimaki – A Japanese appetizer made with thin strips of beef rolled with fresh veggies. Carne Asada – Steak soaked in a citrus marinade, then grilled and sliced into succulent strips. Beef and Broccoli – A savory restaurant-style stir fry that skips the carbs but not the flavor! Lomo Saltado – This beloved Peruvian-Chinese fusion features tender steak strips sauteed with spicy peppers and tomatoes.
