In a small bowl, mix together the spice rub ingredients. Trim the steaks of most of the external fat. Sprinkle both sides of the steaks generously with rub.
Heat a gas grill. Turn one burner to high, another to medium, and another to off. (For a charcoal grill, see tips below).
Sear the steaks on the hottest area of the grill for 2 to 3 minutes on each side. Move to medium-hot (or an unheated area of the grill) if flare-ups occur. When the steaks are seared and grill-marked, move them to a medium-hot area and rotate to create cross-hatched grill marks. Cook for another 4 or 5 minutes, then test for doneness with an instant-read thermometer: 120 to 125°F for rare, 130 to 135°F for medium rare. Continue to grill until done to your liking.
Remove the steaks to a platter and cover lightly with foil. Let the steaks rest for 5 minutes or so before serving.
Notes
If you slash the edges of the steaks in one or two places, it will prevent the steaks from curling up while grilling.
If you have any leftover rub, it can be stored in a close, covered container for up to 3 months.
If using a charcoal grill, arrange coals into 3 areas: a hot area, a medium-hot area and an area with no heat.