Heat oven to 300 degrees F.
Spray muffin tin with gluten free cooking spray or line with paper liners. Set aside.
Combine white rice flour, brown rice flour, oat flour, potato starch, tapioca starch, nonfat milk powder, gelatine, sugar, baking powder, baking soda, salt, and pumpkin pie spice in the bowl of an electric mixer.
Turn on low speed and allow the ingredients to combine thoroughly.
While the flours are being mixed, whisk together the vegetable oil, egg, egg white, pumpkin puree, and vanilla extract.
Pour the wet ingredients into the dry ingredients.
Mix on low speed just until combined.
Increase speed to medium high and mix for 2-3 minutes, until batter is smooth.
Scoop evenly into prepared muffin tin.
Bake for 25 minutes, or until done.