In a saucepan, cook the onions and sprig of thyme in butter over medium-low heat for about 20 minutes, stirring occasionally. Add the maple syrup and continue cooking for 5 to 10 minutes, until the onions are slightly caramelized. Remove the sprig of thyme and set the onions aside.
At the same time, cook the bacon pieces in another pan until crispy (about 5 minutes). Add in the apple, stir and turn off the heat. Set aside.
On a lightly floured work surface, cut the puff pastry sheet into 12 3” x 4” squares. Place the puff pastry squares on a baking sheet lined with parchment paper. Cover the squares with a second piece of parchment paper and cook for 10 minutes or until the pastry is browned.
Take the squares out of the oven and remove the second piece of parchment paper. Sprinkle the squares with the grated Armstrong Old Cheddar Cheese. Cook on the oven’s middle rack for 6 minutes.
Top with the caramelized onions, bacon and apple cubes, then serve.