Heat your oven to 350°F and line a baking sheet(s) with parchment paper (we used 2 baking sheets and baked the 40 cookies in two batches).
In a large bowl, mix together the flour, baking powder, baking soda, cinnamon, pumpkin pie spice, xanthan gum, and salt.
In another large bowl, beat the butter with an electric mixer until it is fluffy, then add the granular erythritol and eggs.
Beat for 1 minute, then add in the pumpkin puree and vanilla and beat again for another minute.
Slowly, add your dry ingredients into the wet ingredients and stir until well combined.
Take the batter 1 tablespoon at a time and spoon it onto the baking sheets.
Wet your finger with water and smooth out the spoonfuls of batter until they are flat 2-inch diameter circles.
Take a small amount of batter and make a stem on each pumpkin circle (see pictures in the post above).
Bake for 12 minutes or until the edges begin to brown.
Let the pumpkin cookies cool completely before assembling the whoopie pies.