Pre-heat oven to 325F degrees and line a muffin tin.
Mix all wet ingredients (bananas, oil, syrup, vanillin a bowl and set aside.
Mix all dry ingredients (flours, baking powder, seasoningtogether in a separate bowl and set aside.
Whisk the dry ingredients into the wet and mix until well combined. Add chopped walnuts and mix well to form a batter.
Scoop/pour the batter into the tin, top with thinly sliced bananas and bake for approximately 35 minutes. This should be moist in the middle and will need to cool for at least 10 minutes prior to serving! You can add some more cinnamon over the top for added flavor!