Blot the Pumpkin: Spread pumpkin puree over paper towels, press gently, and repeat about 2–3 times until thickened to roughly ¼ cup.
Melt the Butter: Melt butter and let it cool for 10–15 minutes. It should be warm, not hot.
Mix Wet Ingredients: Whisk cooled butter, both sugars, egg yolk, and vanilla. Stir in the blotted pumpkin until smooth.
Add Dry Ingredients: Fold in flour, pumpkin pie spice, baking soda, baking powder, and salt just until combined. Don't overmix.
Add Chocolate: Gently fold in the chocolate chips, reserving a few for topping.
Chill: Cover and refrigerate the dough for at least 30 minutes to firm the butter and improve the cookie texture.
Scoop & Shape: Heat oven to 350°F. Scoop about 2 tablespoons of dough per cookie, roll into balls, and gently flatten. Add reserved chocolate chips.
Bake: Bake for 10–12 minutes, until edges are set but centers still look soft. Let cookies continue setting on the hot pan.
Cool & Finish: Cool on the baking sheet for 5 minutes, then transfer to a rack. Sprinkle with flaky sea salt if desired.
