Preheat oven to 350 degrees F.
Line a baking tray with parchment paper.
In the bowl of a stand mixer fitted with the paddle attachment cream together the butter and sugars.
In a separate bowl mix together the flour, cornstarch, nutmeg and cinnamon.
In the stand mixer add in the pumpkin puree and vanilla. Mix until smooth.
Mix in the dry ingredients.
Fold in chocolate chips.
Cover and chill the dough for 30 minutes.
Once chilled, scoop 1 inch balls into the cookie sheet.
Bake cookies for 10-12 minutes.