Combine marinade and dressing ingredients in a small bowl. Marinate steaks in refrigerator for 15 minutes to 2 hours.
Grill steaks and peppers over medium heat until desired doneness; toast bread slices and rub with garlic.
Slice steak thinly, season with salt and pepper. Dice peppers. Layer ingredients in glasses: bread, spinach, peppers, steak, olives, cilantro, and dressing. Top with cheese and garnish.
Notes
Use high-quality ingredients for best flavor. Marinate the steak for at least 15 minutes for optimal tenderness.