Move oven rack to middle positions, and preheat the oven to 350° F. Line two baking sheets with parchment paper or silicone baking mats.
In a large bowl, whisk together the dry ingredients: flour, salt, baking soda, baking powder, and spices.
In a separate large bowl, whisk sugars and oil together. Add pumpkin puree and whisk to combine thoroughly. Whisk in eggs and vanilla until combined.
Sprinkle flour mixture over pumpkin mixture and whisk until completely combined and no flour streaks remain.
Use a cookie scoop with a 1.5-2 tablespoons capacity to drop dough onto prepared baking sheets, about 1 inch apart.
Baking 1 cookie sheet at a time, bake 10-12 minutes, or until a toothpick inserted into the center of a cookie comes out clean.
Remove from the oven and cool on the pan for about 10 minutes. Transfer to wire cooling racks to cool completely. Repeat with the remaining dough.
MAKE CREAM CHEESE FILLING:
In the bowl of a stand mixer fitted with the paddle attachment, beat butter at medium-high speed until smooth with no visible lumps.
Add cream cheese and beat until combined. Add confectioners' sugar, maple syrup, and vanilla and beat until smooth. Be careful not to overbeat filling, or it will thin out. If the filling is too loose, put it in the fridge for about 30 minutes to firm up.
ASSEMBLE:
Turn half of the cooled cookies upside down. Pipe filling onto the flat side of overturned cookies.
Place another cookie, flat side down, on top of filling. Press down slightly so that filling spreads to cookie edges.
Repeat until all cookies are used. If you’re using sprinkles to garnish, hold each whoopie pie in your hand and sprinkle the garnish in the crack of the whoopie pie and turn until all exposed frosting is covered.
Refrigerate at least 1 hour before serving.
Video
Notes
Storage and Freezing Pumpkin Whoopie Pies
Store: Keep in the fridge in an airtight container, layered with parchment if needed. Best within 3 to 4 days.
Freeze: Wrap each pie in plastic wrap and freeze in a container for up to 2 months. You can also freeze the unfilled cookies separately and fill them later.
Thaw: Place in the fridge overnight, or let sit at room temperature (still wrapped) for about an hour.
Make ahead: Bake cookies in advance, freeze, and fill just before serving for the freshest taste.