Combine oil and garlic; let stand 30 minutes.
Preheat oven to 350°.
Brush 1 1/2 teaspoons oil mixture over bread; cut into cubes. Place bread cubes in a single layer on a jelly-roll pan. Bake at 350° for 9 minutes or until toasted.
Steam potatoes, covered, 18 minutes or until tender. Let cool; cut into 1/4-inch-thick slices. Combine potato slices and vermouth; toss gently to coat.
Combine remaining oil mixture, vinegar, and next 7 ingredients (vinegar through parsley) in a bowl. Pour dressing over potatoes; toss gently to coat. Cover and chill.
Serve in a lettuce-lined bowl, if desired. Sprinkle with cheese and croutons.