Combine the oats, oat flour, baking powder and cinnamon in a bowl.
In a separate bowl, mash the banana and in the vanilla, oil and maple syrup. Mix until combined.
Add the wet ingredients to the bowl with the dry ingredients and mix until combined.
Mix together until well combined and press this mixture into the bottom of a loaf pan. Bake for 8-10 minutes until the base sets.
While it is baking, cook down the berries in a pan with a little squeeze of lime juice until it becomes a jelly-like consistency. Add a little maple syrup to the berries for a little extra sweetness if desired. Allow the mixture to cool for a few minutes.
Mix together oats, oil and cinnamon in a bowl and set aside.
Pour the berry mixture on top of the base and sprinkle the cinnamon oat mixture on top.
Return the pan to the oven and bake for another 15-20 minutes until golden brown on top. Allow it to cool completely before slicing into bars.
Notes
Model-authored article prose will add serving, storage, and optional variation guidance without changing the primary recipe.