Toast topped with asparagus and two types of cheese makes for a rustic appetizer; truffle oil adds a luxurious note.
Heat grill or broiler. Grill bread slices until golden on both sides. Rub one side with garlic; brush lightly with oil.
Preheat oven to 350 degrees. Bring a large saucepan of water to a boil over high heat; add salt generously. Add asparagus, and cook until tender, about 3 minutes. Drain asparagus, and set aside.
Place toasted bread on a baking sheet, and sprinkle fontina evenly over slices. Arrange about 3 to 4 asparagus spears on top of each. Sprinkle Parmesan over asparagus, dividing evenly.
Bake until cheese has melted, about 10 minutes. Remove from oven, and drizzle with truffle oil, if using.
Truffle oil can be found at most gourmet shops.