In a small bowl whisk together the ingredients for the marinade. Season the chicken with salt and pepper and pour the marinade over the chicken. Refrigerate for at least an hour.
Preheat grill to medium-high heat and brush the grill grates with oil. Place the marinated chicken onto the grill and cook for 4-6 minutes, then flip over and cook another 4-6 minutes or until cooked through (165 degrees F). Remove the chicken from the grill and let it rest.
Chop romaine hearts and slice chicken into strips.
Assemble Caesar salad starting with a bed of romaine lettuce then add the slices of grilled chicken, croutons, Caesar dressing, shredded Parmesan cheese, and season with salt and freshly ground black pepper.
If you don't have a fresh lemon or rosemary on hand, this recipe would also be delicious with a simple chicken marinade of olive oil, salt, and pepper.