Step 1: Preheat your oven to 350°F (175°C).
Step 2: Line your baking sheet with parchment paper.
Step 3: In a medium bowl, whisk together the oats, flour, baking powder, baking soda, pumpkin pie spice, and salt. Set aside.
Step 4: In a large mixing bowl, cream together the butter, dark brown sugar, and granulated sugar until light and fluffy.
Step 5: Add vanilla extract, egg yolk, and pumpkin puree to the butter mixture and mix well.
Step 6: Gradually add the dry mixture to the wet ingredients, mixing until just combined.
Step 7: Fold in the chocolate chips.
Step 8: Using a scoop, drop dough onto the prepared baking sheet, leaving space between cookies. Bake for 10-12 minutes.
Step 9: Cool on the baking sheet for a few minutes before transferring to a wire rack.
