Preheat the oven to 350°F and lightly grease a standard 12-cup muffin tin with nonstick spray.
Roll one sheet of crescent dough into an even rectangle on a lightly floured surface, sealing seams if needed.
Spread softened butter evenly over the dough.
Mix the sugar and cinnamon together, then sprinkle evenly over the buttered dough, pressing gently to adhere.
Roll the dough tightly from the long edge into a log.
Cut the log in half crosswise, then slice each half lengthwise to expose the layers.
With the layered side facing outward, roll each piece into a loose spiral and place into the muffin tin.
Repeat with remaining dough sheets until all muffin cups are filled.
Bake for 18–20 minutes until puffed and golden brown.
Remove from the oven and immediately roll each cruffin in remaining cinnamon sugar before serving.
