GRILL DIRECTIONS: In small bowl, combine all butter ingredients; blend well. Place butter on piece of plastic wrap; shape into 4-inch log. Refrigerate 1 hour or until firm.
Meanwhile, use 1 tablespoon melted butter, brush both sides of steak; rub each side of steak with 1 teaspoon blackened steak seasoning. Let stand at room temperature for 30 minutes.
Heat grill. When ready to grill, place steak on gas grill over medium heat or on charcoal grill 4 to 6 inches from medium coals. Cook 8 to 20 minutes or until of desired doneness, turning once.
If necessary, let butter stand at room temperature for about 15 minutes to soften. To serve, cut steak into 4 serving pieces; place on individual serving plates. Cut butter into 4 slices; place on center of hot steaks. Serve immediately.