Preheat oven to 325° & line 2 baking sheets with parchment paper. Set aside.
Melt the 4 tablespoons of butter & set aside to cool.
Whisk together flour, baking powder, baking soda, salt, pumpkin pie spice, and cinnamon. Set aside.
With your mixer, whisk together brown sugar, 1/2 cup granulated sugar, eggs, pumpkin puree, and vanilla until smooth. Add cooled butter & whisk until combined. Fold in your dry ingredients with a spatula until completely mixed in. Rest the dough for 10 minutes.
Add 1/2 cup of granulated sugar & 1/2 cup of powdered sugar to 2 separate bowls for rolling your cookies
Using a cookie scoop, or roughly 1 tablespoon of dough, drop dough into your granulated sugar bowl and push it around to cover it with the granulated sugar. Once covered in granulated sugar roll it around in your hands to form a ball. The dough will feel light and airy as you roll it around and won't form a stiff ball.
Drop dough ball into powdered sugar and roll around to coat.
Set dough balls onto your prepared cookie sheets about 2 inches apart.
Bake for 14 minutes until cracks have formed.
Remove cookies from the oven and allow to cool on the baking sheet for 10 minutes before transferring to a wire rack.