Preheat oven to 375 degrees.
In a large bowl, blend sugar and butter.
Add egg, then pumpkin and blend until well combined.
Add flour, baking soda, baking powder, cinnamon and salt. Mix by hand until combined.
Put batter into a gallon sized ziplock bag.
Cut ½ inch off of one corner. Pipe 1-2 inch circles of batter onto a parchment lined cookie sheet. I draw circles on the underside of the parchment as a guide for the batter.
Bake for 12-15 minutes until whoopies are slightly browned. Remove from oven and let cool completely before filling.