How to Make It
Preheat grill to 350° to 400° (medium-high) heat. Whisk together first 4 ingredients in a medium bowl.
Sprinkle 1 tsp. salt and 1/2 tsp. pepper over steak. Grill steak, covered with grill lid, 8 to 10 minutes on each side or to desired degree of doneness. Brush steak with olive oil, using rosemary sprigs as a basting brush. Let stand 10 minutes.
Meanwhile, preheat broiler with oven rack 7 inches from heat. Toss together broccoli, next 2 ingredients, and remaining 1 tsp. salt and 1/2 tsp. pepper in a large bowl. Spread broccoli mixture in a single layer in a jelly-roll pan, and broil 3 to 5 minutes or until charred and tender. Transfer to large bowl.
Toss together broccoli mixture and lettuce. Cut steak diagonally across the grain into thin strips. Arrange steak on a serving platter; top with broccoli mixture. Sprinkle with fried onions, and serve with dressing.