Preheat the oven to 350°F, or 320°F fan. Line a 2-pound loaf pan with parchment paper.
Add the bananas, coconut oil, eggs, maple syrup or honey, vanilla, and salt to a food processor or blender. Blend until smooth.
Add the oats, almond flour, cinnamon, baking soda, and baking powder. Blend until fully combined.
Pour the batter into the prepared loaf pan. Sprinkle the chopped walnuts evenly over the top.
Bake for 50 to 60 minutes, until a skewer inserted into the center comes out clean.
Cool in the pan for 10 minutes. Transfer to a wire rack and cool completely before slicing.