Pre-heat oven to 400 degrees F. Line a baking sheet with parchment paper.
Place the baguette slices on the baking sheet, spacing them out. You may need to do this in batches. Put 1-2 pieces of brie cheese on each slice. Cook in the oven for 6-8 minutes, or until the brie is bubbly and the bread is toasted.
Remove from oven and top with an apple slice and crumbled bacon. Drizzle maple syrup on top just before serving.