Add heavy cream to a stand mixer and whip on med to medium high speed until soft peaks. (usually about 2 minutes)
While the cream is mixing, place pumpkin puree, cinnamon, and all-spice in a bowl. Stir until combined.
Once cream is at soft peak stage, add powder sugar in a 1/2 cup at a time. After one cup, turn off mixer. Gently fold in pumpkin puree mixture to cream. If the consistency is not firm enough, add more powder sugar, about a 1/4 cup at a time until you reach desired consistency.