1 large head romaine lettuce, cut into bite-size pieces
Whisk mayonnaise, chicken broth, soy sauce, lemon juice, chipotles and brown sugar in medium bowl to blend. Season dressing to taste with salt and pepper. (Dressing can be prepared 1 day ahead. Cover and refrigerate.)
Mix lettuce, tomatoes and corn in large bowl. Add dressing and 2 tablespoons Parmesan cheese and toss to coat. Sprinkle with remaining 2 tablespoons Parmesan cheese and serve.