Preheat oven to 350 degrees F. Line 2 (12 count) muffin tins with paper liners and set aside. Combine the sugar and cinnamon in a small dish and whisk until evenly incorporated.
Unwrap the crescent dough and separate the dough into 24 triangles.
Dip each marshmallow into the melted butter, then coat the marshmallow in the cinnamon and sugar mixture. Place the coated marshmallow at the base of the triangle, and wrap it in the dough. Roll it tightly, pinching any seams together.
Place the dough, seam-side down in the prepared muffin tin. Place a sheet of foil on the rack below the muffin tins to catch any dripping marshmallow that might escape and bake the rolls for 13 to 15 minutes, until golden brown on top.
Let the rolls cool slightly before carefully removing them from the muffin tin. Keep the rolls in the liners until you're ready to enjoy.
For The Icing
Combine the icing ingredients in a small dish and whisk together until smooth. Spoon the icing over the warm rolls and enjoy!
Notes
These rolls can also be baked on a parchment lined baking sheet outside of the muffin liners.Cleaning up melted on marshmallow is super easy, just soak in warm water for a minute and it'll come right off!