For the Vinaigrette, mix vinegar, Seasoning and sugar in small bowl with wire whisk. Slowly whisk in olive oil until well blended. Set aside.
For the Steak Salad, rub Seasoning evenly on both sides of steak. Heat oil in large skillet on medium-high heat. Add steak; cook 2 to 3 minutes per side or until desired doneness. Let stand 5 minutes before slicing.
Divide salad greens evenly among 4 serving plates. Top each with sliced steak and desired toppings, such as sliced red onions, crumbled blue cheese and chopped tomatoes. Drizzle with Vinaigrette before serving.