Preheat oven to 400° F. Line a baking sheet with aluminum foil. Place a wire rack on top of this and coat the rack with nonstick cooking spray. Lay 1 piece of bacon on the rack and bake for 17-20 minutes, until the bacon is very crispy. Blot the bacon with a paper towel. Cool on rack until you can easily handle, and then crumble the bacon into little bits. Set aside.
Meanwhile, thinly slice the baguette. Place slices on a greased baking sheet and place in 400° F oven for 5 minutes, until the edges are golden brown and crisp.
Top each toasted slice of bread with Swiss cheese, to taste.
Place back in the hot oven until cheese is melted (should only take a couple minutes).
Top with crumbled bacon, a touch of pepper, and drizzle with truffle oil.