Remove the steak from the refrigerator and let it come to room temperature for about 30 minutes. Pat it dry with paper towels to remove any moisture.
Season both sides of the steak with sea salt and cracked pepper, pressing it into the meat to adhere.
Place your cast iron skillet over high heat. Allow it to get very hot, which is crucial for a good sear.
Once the skillet is hot, add 1 tablespoon of oil, swirling it around to coat the bottom evenly. The oil should shimmer immediately.
Carefully place the steak in the skillet, laying it away from you to avoid splatter. Let it sear for 4-5 minutes without moving it.
Using tongs, flip the steak. Add 1 tablespoon of unsalted butter, 5 crushed garlic cloves, and 3 sprigs of fresh thyme to the pan. As the butter melts, tilt the pan slightly and spoon the melted butter over the steak for added flavor.
Cook for an additional 3-4 minutes for medium-rare. Use an instant-read thermometer to check the internal temperature; aim for 130°F (54°C).
Transfer the steak to a cutting board and cover it loosely with foil. Let it rest for at least 5 minutes to allow juices to redistribute.
Once rested, slice your steak against the grain and serve it with the pan juices drizzled over the top.
