Position the rack in the center of the oven and preheat to 325 degrees F.
03Bake the cinnamon rolls uncovered until the tops are golden brown, about 25 minutes. Meanwhile, whisk the powdered sugar, mascarpone cheese, and buttermilk in a medium bowl until smooth and creamy.04Brush the remaining 1 tablespoon of butter over the baked cinnamon rolls and then drizzle the cheese mixture over top. Serve warm.