Trim fat from steak. Sprinkle both sides with salt and black pepper. Prepare grill or broiler. Place steak on grill rack or broiler pan coated with cooking spray; cook 8 minutes on each side or until desired degree of doneness. Cut steak across grain into thin slices; cut slices into 2-inch pieces. Set aside.
Combine vinegar and next 4 ingredients (vinegar through red pepper) in a small bowl. Combine steak, lettuce, bean sprouts, and bell pepper in a large bowl; toss well. Drizzle vinaigrette over salad; toss to coat.