Preheat oven to 350°F. Line a 12-count muffin pan with cupcake liners and set aside.
In a large mixing bowl, whisk together the flour, baking powder, baking soda, pumpkin pie spice, cinnamon, and salt. Set aside.
In a separate mixing bowl, mix together the pumpkin puree, oil, brown sugar, granulated sugar, eggs, and vanilla extract until fully combined. Add the wet ingredients to the dry ingredients and mix until just combined, making sure not to over mix the batter.
Evenly distribute the batter between all 12 cupcake liners, only filling them about 2/3 of the way full, and gently smooth out the batter on top. Bake at 350°F for 16-20 minutes or until a toothpick inserted into the center of the cupcake comes out clean.
Remove from the oven and allow to cool for a few minutes. Remove the cupcakes from the pan and transfer to a wire rack to cool completely.
To make the nutella frosting:
In the bowl of a stand mixer fitted with the paddle attachment, or in a large mixing bowl using a hand-held mixer, beat the butter on medium speed for 1-2 minutes until smooth. Add in the Nutella and continue mixing for an additional minute until well combined. Add in the powdered sugar, heavy cream, vanilla, and salt and continue mixing on medium speed until fully combined, scraping down the sides of the bowl as needed.
Pipe the frosting on the cooled cupcakes as desired.