Let the tomahawk steak sit at room temperature for about 30 minutes.
Season the surface of the meat with salt and pepper.
Heat a pan over high heat with olive oil.
Sear the tomahawk for 2–3 minutes on each side.
Add garlic, rosemary, and butter, then baste both sides with the butter for another 5–10 minutes.
Wrap it in foil and let it rest for 5 minutes.
Slice into pieces of your desired thickness.