Preheat oven to 350°F. Line two baking sheets with parchment paper.
In a large bowl whisk together the brown sugar, oil, pumpkin, egg, and vanilla until well combined.
Whisk together the flour, baking powder, baking soda, salt, ground cinnamon and pumpkin pie spice. Add the dry ingredients to the wet ingredients and mix well.
Using an ice cream scoop or tablespoon, drop evenly sized scoops of batter onto the prepared cookie sheets 2 inches apart each, making 16 scoops total.
Bake 10-15 minutes, until the cakes are springy. Let cool completely.