Add the milk to a microwave safe bowl and heat for 45 seconds. (The temperature should be about approximately 100-110 degrees F).
Add in the honey and sprinkle the yeast on top. Let sit for about a minute and add the melted butter, room temperature egg, and pumpkin puree. Mix together until combined with a wooden spoon.
In the bowl of an electric mixer with the paddle attachment, combine flour, pumpkin pie spice and salt.
Mix on low briefly to combine. Add the pumpkin milk mixture and mix on low until a dough begins to form. About 2 minutes.
Switch out the paddle attachment for the dough hook and knead the dough for about 5-6 minutes. The dough will be sticky.
Use a spatula to transfer the dough into a greased large bowl. Cover loosely with a dish towel and let proof for 1 hour. The dough should double in size.
Grease a 9X13 inch pan and line it with parchment paper.
Once the dough has proofed, place it on a floured work surface and use a rolling pin to roll it into a roughly 12X16 inch rectangle.
Use a small spatula to spread the room temperature butter onto the dough leaving about ½ border on the longer side.
Sprinkle the brown sugar evenly over the top, pressing it lightly into the butter. Roll the dough starting from the shorter side and pinch the seam. Use a serrated knife to cut the dough in 12 equal size rolls. You will probably need to cut off the ends of the dough as they won’t be as filled with sugar.
Place rolls cut side up into the prepared pan and cover loosely with a dish towel for 25 minutes to let the dough proof once more.
Preheat the oven to 350 degrees F. Bake for 25-28 minutes.
While the rolls bake, make the mascarpone icing. Use a stand or hand mixer to beat the ingredients together until smooth and fluffy.
Remove the pumpkin cinnamon rolls from the oven and let them cool in the pan for a few minutes. Use a spatula to top the rolls with mascarpone icing, sprinkle extra pumpkin pie spice and enjoy!