Rub the meat with a cut clove of garlic and brush with the rosemary then season with the salt, pepper, and onion powder and drizzle with the olive oil.
Allow to come up to room temperature.
Get your grill up to temperature and cook the steak to your liking, checking the internal temperature to be sure.
Remove the meat and allow it to rest for 5-10 minutes, anointing it with a knob of butter.