1. Preheat broiler.
2. Cut roll diagonally into 4 (1/4-inch-thick) slices. Trim end pieces so that bread lies flat, and discard end pieces.
3. Combine butter, parsley, and thyme; spread evenly onto 1 side of each bread slice. Top with cheeses. Place bread on a baking sheet; broil 1 to 2 minutes or until cheese melts.