1Set oven control to broil. Spray broiler pan with cooking spray. Place steak on broiler pan; brush with 1 tablespoon of the dressing. Broil with top about 4 to 6 inches from heat 10 minutes. Turn steak over; brush with another 1 tablespoon dressing. Broil 5 to 10 minutes longer or until meat is desired doneness (145°F for medium-rare). Cover; let stand 5 minutes.
2Meanwhile, on each of 4 serving plates, evenly divide spinach and tomatoes. Thinly slice steak across the grain; arrange over salads. Top with cheese. Drizzle with remaining dressing, about 2 tablespoons on each salad.