Prep the pumpkin: Spread the pumpkin puree between several paper towels and gently press to remove excess moisture. You should end up with roughly ⅓ cup of thick pumpkin puree. Don't skip this! Removing excess moisture keeps the cookies thick and chewy instead of cakey.
1/2 cup 100% pumpkin puree
Cream butter and sugar: Using a stand mixer fitted with the paddle attachment, cream the butter and sugar for 2-3 minutes until light and fluffy. Start Timer
1 cup unsalted butter, 1½ cups granulated sugar
Add wet ingredients: Mix in the egg yolk, blotted pumpkin, vanilla, and milk. Mix just until combined.
1 large egg yolk, 2 tsp. vanilla extract, 1 Tbsp. whole milk
Combine dry ingredients: Whisk together the flour, baking powder, baking soda, salt, pumpkin pie spice, and cinnamon. Add to the wet ingredients and mix on low just until no flour streaks remain. Do not overmix.
2¾ cups all-purpose flour, 1 tsp. baking powder, 1/4 tsp. baking soda, 3/4 tsp. kosher salt, 1½ tsp. pumpkin pie spice, 1/4 tsp. cinnamon
Chill: Cover and refrigerate the dough for just about 10 minutes to make it easier to scoop and roll. Start Timer
Roll: Preheat oven to 350°F. Line a few baking sheets with parchment paper or silicone baking mats. Combine the sugar and pumpkin pie spice in a small bowl. Scoop dough into approximately 2-Tbsp cookies and roll each ball in the spiced sugar.
1/4 cup granulated sugar, 1 tsp. pumpkin pie spice
Bake: Bake for ~10 minutes Start Timer until edges are just set and the centers look slightly underbaked The cookies should not brown. Cookie scoot then afterwards if they are a little wonky shaped and top with any remaining spiced sugar for a finishing look.
Cool: Allow cookies to cool on the baking sheet for 5-10 minutes before transferring to a cooling rack Start Timer. They might seem underdone, but as they cool completely, they become perfectly soft, chewy, and so yummy!