I found the original recipe for this on Pinterest, I take no claim for the recipe as my own. I did however add one little thing to it to sort of make it my own. I love pumpkin and snickerdoodles have sort of started to grow on me within the past couple years. Adding the two together was just simply amazing. I made these cookies about two-three times last year in the fall. I can't wait for fall to return so I can make these cookies again! In the original recipe it didn't call for pumpkin pie spice. So, I added it to both the batter and the coating. I also omitted salt from the original. Enjoy!
In a medium bowl, combine flour, baking powder, salt, cinnamon, nutmeg, and pumpkin pie spice. Whisk together to blend. In a large bowl, beat together butter and sugars on medium speed until well combined. Next, still on medium speed, beat in pumpkin. Then, add the egg and vanilla extract. Lastly, add in the dry ingredients. Beat until combined, but do not over mix. Cover the dough, and refrigerate for one hour, until firm.
Preheat oven to 350 degrees.
Line baking sheets with parchment paper. In a small bow, mix together the sugar and spices for the sugar coating. Scoop dough (approximately 2 1/2 tablespoons) and roll into a ball. Rol the dough ball in the sugar mixture, and place on the lined baking sheet, leaving about 2 inches between each cookie. Take a drinking glass with a flat bottom and moisten with water. Dip the glass in the sugar mixture, and use it to flatten the dough balls. Re-sugar the glass as needed.
Bake the cookies for 10-12 minutes (no longer than that. Depending on your oven it make take 10 or the max 12. I did mine at 11 minutes). Remove when the centers of the cookies have set. Let cool on the baking pan for approximately 5 minutes, and then transfer to wire cooling racks to cool completely.