Preheat oven to 350 degrees. Line 8 wells in a muffin tin with baking cups (for easier clean up) or spray the wells with non-stick cooking spray.
Unroll crescent dough and divide into 8 triangles at the perforations.
In a small bowl, mix together the cinnamon and sugar.
Dip a marshmallow into the melted butter.
Then roll the marshmallow in the cinnamon sugar.
Place the coated marshmallow on the large end of the crescent triangle.
Fold the dough over the marshmallow tightly sealing the edges so the marshmallow does not melt and leak.
Finish wrapping the dough around the marshmallow and form into a ball.
Repeat with the other marshmallows. Place the rolls in a muffin tin. Brush the rolls with some of the remaining melted butter. then sprinkle the remaining cinnamon sugar over the rolls.
10. Bake the rolls for 10 to 14 minutes until puffed and lightly golden. Remove from oven and allow to cool slightly before serving.