Preheat the oven to 350°F and adjust the oven rack to be in the middle of your oven. Then prep a loaf pan with parchment paper and baking spray.
Place the brown sugar, vanilla, and eggs into a medium sized mixing bowl.
Whisk the sugar, vanilla, and eggs together until smooth.
Next, add the vegetable oil, pumpkin puree, and oat milk to the batter.
Whisk together until the batter is smooth.
In a separate medium sized bowl, whisk together the gluten free flour, baking powder, salt, cinnamon, and pumpkin pie spice.
Add the dry ingredients to the wet ingredients and gently whisk together until combined and no lumps remain.
Pour the batter into the prepared loaf pan.
Bake for 1 hour and 15 minutes or until the loaf is baked all the way through. Use a toothpick to test the doneness of the loaf, it should come out completely clean or with a few crumbs attached to it.
Let the loaf cool completely and enjoy!