In a medium bowl, whisk together the flour, baking powder, salt, cinnamon, and nutmeg. In the bowl of an electric mixer, beat together the butter and sugars on medium-high speed until light and fluffy, 2-3 minutes. Add the the pumpkin puree and continue mixing. Beat in the egg and vanilla until incorporated, scraping down the sides and bottom of the bowl as needed. With the mixer on low speed add in the dry ingredients and mix just until incorporated. Cover and chill the dough for at least 1 hour.

When ready to bake, heat the oven to 350˚. Line baking sheets with silicone baking mats or parchment paper. Combine the sugar, cinnamon and nutmeg in a bowl and mix to blend. Use a cookie scoop (about 2½ tablespoons) to scoop out the dough. I prefer to scoop an entire sheet, then roll them into balls. When you’ve got a full sheet of dough balls, roll each in the cinnamon sugar mixture to coat. Place on the prepared baking sheet about 2 inches apart. Dip the bottom of a flat drinking glass in water and then into the cinnamon sugar. Press on each ball to flatten slightly. Recoat the glass as needed.

Bake the cookies for 10-13 minutes, or until just set and baked through. Let cool on the baking sheets about 5 minutes, then transfer to a wire rack to cool completely. Repeat with the remaining dough. Store in an airtight container.