Preheat your oven to 375°F (190°C). Line a baking sheet with parchment paper.
In a small bowl, mix cinnamon and sugar.
Unroll crescent dough and separate into 8 triangles.
Flatten each triangle slightly to ensure it wraps around the marshmallow completely.
Dip a marshmallow into melted butter, then roll in the cinnamon-sugar mixture until fully coated.
Place the marshmallow on the wide end of a dough triangle.
Wrap the dough around the marshmallow, pinching all seams shut tightly to seal.
Place seam-side down on the baking sheet. Repeat with remaining buns.
Optional: Brush the tops with extra melted butter and sprinkle with cinnamon sugar.
Bake for 12–15 minutes, or until golden brown.
Let cool for 5 minutes before serving—the centers will be hot and gooey!
