Preheat oven to 350°F (175°C) and line two baking sheets with parchment paper.
In a large bowl, whisk together melted butter, pumpkin purée, brown sugar, granulated sugar, egg yolk, and vanilla extract until smooth.
In a separate bowl, whisk together flour, baking soda, baking powder, cinnamon, pumpkin pie spice, and salt.
Gradually mix the dry ingredients into the wet mixture until just combined. Fold in chocolate chips.
Scoop tablespoon-sized portions of dough onto prepared baking sheets, spacing 2 inches apart.
Bake for 10–12 minutes, until edges are set but centers look slightly soft (they’ll firm up as they cool).
Cool on the baking sheet for 5 minutes, then transfer to a wire rack.
Serve warm or store in an airtight container.
Prep Time: 10 minutes | Cook Time: 12 minutes | Total Time: 22 minutes
Kcal: Approx. 160 per cookie | Servings: 24