To grill: Prepare outdoor grill with medium-hot coals, or heat gas grill to medium-high. Season steaks on both sides with a coating of kosher salt and pepper. Grill steaks, covered, about 6 minutes per side or until instant-read thermometer inserted in center registers 145 degrees for medium-rare.
During the last 2 minutes of cooking, top each steak with 2 ounces of bleu cheese and close the lid on the grill. Remove steaks from grill, let rest for 5 minutes before serving.
To broil: Heat oven to broil. Grease broiler-pan. Broil steaks about 6 minutes on each side for medium-rare. Top each steak with bleu cheese crumbles. Broil additional 30 seconds.