Preheat oven to 400 degrees. In a small saucepan, melt butter in oil over moderate heat. Brush mixture onto 1 side of each bread slice. Arrange slices, buttered side up, on a baking sheet and bake for 5 minutes or until golden
Preheat broiler. Sprinkle fontina and Parmesan cheeses evenly over toasts. Broil about 4 inches from the heat for 1 minute, or until fontina begins to melt.