Preheat the oven to 180C/350F. Line a large tray or cookie sheet with parchment paper and set aside.
In a large mixing bowl, mix your dry ingredients and set aside. In a separate bowl, whisk together your sugar and oil, until glossy. Add in your milk and vanilla extract and mix until combined. Gently fold through your dry ingredients and mix well. Using a rubber spatula, fold through your chocolate chips.
Using a cookie scoop or large spoon, scoop out 12 balls of cookie dough and place them on the lined pan. Sprinkle with extra pumpkin pie spice and bake the cookies for 12-15 minutes, or until the edges begin to go golden.
Remove from the oven and allow to cool on the tray completely.
TO STORE: Pumpkin cookies can be stored at room temperature, in a sealed container, or completely covered. The cookies will keep fresh for up to 5 days. Refrigerate them if you'd like them to keep for longer. TO FREEZE: Wrap each cookie in parchment paper and place it in a ziplock bag or shallow container. Store in the freezer for up to 6 months. Once ready to eat, thaw out to room temperature.