Step 1

Score flank steak 1/4 inch deep across the grain on both sides. Season with salt and pepper on both sides.

Step 2

Vacuum seal steak or seal in a plastic zip top bag using the water displacement method to remove all of the air from the bag with the steak.

Step 3

Fill a large pot or water container will water and insert sous vide circulator. Set temperature to 131 degrees for medium rare. (Can set to a higher or lower temperature, depending on personal preference.

Step 4

Submerge vacuum sealed steak in sous vide water, ensuring entire steak is covered with water. Set time to 90 minutes.

Step 5

When cooking time is complete, remove steak from bag and pat dry. Sprinkle with additional salt and pepper if desired for taste.

Step 6

Set a cast iron or stainless steel skillet over very high heat and add butter. Just when the butter starts smoking, lay flank steak in pan. Sear on each side for 1-2 minutes.

Step 7

Remove from pan and slice against the grain in thin slices to serve.