Liberally season the steak with salt. Place the steak and 1 tbsp of butter in a vacuum-sealed bag. Place the bag in a hot water bath for 1 hour and 15 minutes at 129°F (54°C) for medium-rare and 135°F (57°C) for medium.
In a pan set to medium-high heat, add the butter, garlic, and thyme. Remove the steak from the vacuum-sealed bag and sear each side in the butter mixture until golden brown. About 2-3 minutes per side.
Let the steak rest for about 3 minutes. Slice against the grain and top with salt and fresh-cracked black pepper.