1. In a large bowl, toss beef with vinaigrette; let stand 15 minutes. In a small bowl, mix yogurt and lime juice.
2. In a large skillet, heat oil from sun-dried tomatoes over medium-high heat. Add pepper and onion; cook and stir until crisp-tender, 3-4 minutes. Remove to a small bowl; stir in sun-dried tomatoes and olives.
3. Place same skillet over medium-high heat. Add beef; cook and stir until no longer pink, 2-3 minutes. Remove from pan.
4. Serve steak and pepper mixture in tortillas; top with cheese. Serve with yogurt mixture and lime wedges.
