Preheat oven to 350 and grease a bread pan well or add parchment paper.
In a blender or food processor, make oat flour by grinding oats into a fine flour, and place into bowl.
Add GF flour, baking soda, baking powder, salt, to ground oats and stir.
In the food processor, add banana, fresh blackberries, melted butter, eggs, and maple syrup. Blend for 1-2 minutes until completely combined and smooth.
Stir wet ingredients into dry ingredients and pour into bread pan.
Bake for 45-60 minutes until you can insert a toothpick and it comes out clean.
Allow to cool on cooling rack.