4 tablespoons extra-virgin olive oil, plus more for drizzling
5 sprigs fresh rosemary
3 cloves garlic, smashed
2 sprigs fresh thyme
Flaked sea salt, for sprinkling
Rub the steak all over with 1 tablespoon olive oil, 2 sprigs rosemary, 1 clove garlic and 1 sprig thyme. Cover and refrigerate for at least 4 hours and up to 8 hours.
Let the steak stand at room temperature for 1 hour before cooking.
Preheat the oven to 250 degrees F.
Heat a medium cast-iron pan over high heat. Season the steak all over with kosher salt. Add the remaining 3 tablespoons olive oil to the pan and immediately place the steak in the pan. Cook, undisturbed, until a nice dark crust forms, 3 to 4 minutes. Flip the steak over and sear the other side. Transfer the steak to a plate. Remove the pan from the heat and let cool slightly, about 3 minutes.
Put the remaining 3 sprigs rosemary, 2 cloves garlic and 1 sprig thyme into the pan and place the steak on top of the herbs. Transfer to the oven and cook, flipping the steak every 10 minutes, until an instant-read thermometer inserted into the thickest part of the steak reads 120 degrees F for medium rare, about 1 hour. Let rest for 15 minutes on a cutting board.
To carve, run your knife along the bone to cut away the meat. (Reserve the bone for plating.) Cut the steak at a 45-degree angle into 1/2-inch slices. Place the meat next to the bone on a large plate, sprinkle with sea salt and drizzle with olive oil.