Preheat oven to 400. Put muffin chunks on baking pan. Toast in oven til golden brown, turning once to prevent burning, about 5 to 10 minutes. Let cool. Do not prepare more than 2 hours ahead. In small bowl, whisk together mayonnaise, vinegar, and seasoning. Refrigerate until ready to use. Toss lettuce with dressing in large bowl. Put dressed lettuce on large serving platter or in individual plates. Top lettuce with each of the remaining ingredients, in order. Top with corn muffin croutons. Serve at once. Makes 6 to 8 servings.