Use any combination of your favorite lettuces for this savory salad. If you can't find Comté, substitute a fragrant Gruyère or Beaufort. Prep: 25 minutes; Cook: 5 minutes; Broil: 3 minutes.
Preheat oven to broil. Place bread on baking sheet, and cover each piece with 2 to 3 Comté slices. Broil 3 minutes 6 inches from heat source or until cheese melts and is bubbly and brown.
Toss onion and next 5 ingredients gently with Balsamic Vinaigrette.
Sauté mushrooms in oil 5 minutes or until tender. Top salad with mushrooms and bread rounds. Serve while cheese and mushrooms are warm.