Preheat oven to 450°. Unfold and cut puff pastry sheets in half lengthwise, and cut each half crosswise into 1-inch-wide strips. Place strips on a lightly greased parchment paper-lined baking sheet. Bake 10 minutes or until golden brown.
Meanwhile, combine sugar and cinnamon. Remove pastry strips from oven, and dip in butter; roll in cinnamon-sugar mixture. Let stand on a wire rack 5 minutes or until dry.