Step 1

Set up your sous vide cooker: Fill your sous vide container or large pot with water and turn on the sous vide machine and set the temperature according to the manufacturer's instructions to 130° F (54.4° C) for medium-rare, or to the desired finished temperature.

Step 2

Season the steak: Liberally salt all sides of the steak with kosher salt and pepper. Place a few thyme sprigs or other aromatics on the steak if desired.

Step 3

Vacuum seal the steak: Place the steak in a vacuum seal bag or Ziplock bag and vacuum seal the bag if using a vacuum sealer. If using a Ziplock bag, partially seal it after removing as much air as possible, then use the water displacement method by placing the bag in the water (always keeping the opening above the water line) to push the rest of the air out before sealing it.

Step 4

Cook the steak: Fully submerge the bag in the water bath, clipping it to the side of the container to keep it in place, then cook for 1 and 3 hours for a 1-inch-thick steak.

Step 5

Remove the bag from the water bath and let the steak sit on the counter in the bag for 10 to 15 minutes to cool slightly before searing.

Step 6

Remove the steak from the bag and pat dry with paper towels.

Step 7

To sear the steak in a skillet: Heat a cast-iron skillet over high heat until it just starts to smoke. Drizzle enough oil to coat the bottom of the pan and let that heat up for a few seconds.Place the steak in the skillet and sear for about 30 to 60 seconds on each side until golden brown. Going longer than 1 minute on each side can cause the steak to cook more than desired.

Step 8

Optional: To butter-baste the steak during the sear, add up to a few tablespoons of butter along with thyme sprigs and crushed garlic cloves after the steak is searing. Once the butter melts, begin basting it over the steak with the thyme until finished with the sear.

Step 9

Slice and serve immediately with a sprinkle of finishing salt, if desired. There's no need to rest sous vide steak.