Mix cinnamon and sugar in a small bowl. Preheat oven to 160 °C (320 °F).
Cut puff pastry into 5 mm wide strips. Line a baking sheet with parchment paper and place strips on it. Brush with melted butter. Sprinkle with half the cinnamon-sugar mixture.
Twist each pastry strip into a spiral shape.
Sprinkle remaining cinnamon-sugar mixture over the spirals.