Preheat oven to 350°F. Line two baking sheets with parchment paper; set aside.
Make the spiced sugar: In a medium bowl, whisk together the granulated sugar with pumpkin pie spice. Set aside
Remove excess liquid from the pumpkin puree: Spread the pumpkin puree out on a plate. Gently blot with paper towels, pressing down lightly, to soak up excess liquid. Repeat with paper towels until you're left with about ¼ cup of thick pumpkin puree. Discard the towels with excess liquid and set aside the plate with the pumpkin puree..
Whisk together the dry ingredients: In a large bowl, whisk together the flour, pumpkin pie spice, baking soda, baking powder, and kosher salt. Set aside.
In a stand mixer (or in a large bowl using a hand mixer) cream together the butter and brown sugar for 2-3 minutes. Add the egg yolks and vanilla and beat together for 1-2 minutes more, until the mixture is light and fluffy. Add in the pumpkin puree and mix together on low just until combined.
Add in the dry ingredients. Mix together on low just until combined. Do not overmix!
Using a medium cookie scoop, scoop batter into a ball and then roll gently into the spiced sugar mixture. Place on the prepared cookie sheets about 2 inches apart.
Bake at 350°F for 12-14 minutes, just until the edges are slightly darkened. The centers will be soft. Allow to cool on the pans for 10-15 minutes.