Preheat the oven to 350 degrees Fahrenheit. Grease a 9x5 loaf pan with coconut oil and then line with parchment paper.
Combine the mashed bananas and maple syrup in a medium bowl. Using an electric mixer, mix on low to medium speed until incorporated. Add the remaining ingredients to the bowl and mix until thoroughly combined (the batter will be thick).
Pour the batter into prepared pan and smooth top with a spatula. Sprinkle sesame seeds and/or walnuts on top if desired.
Bake for 45-55 minutes or until a tester comes out clean (50 mins was just about right for my oven). During the last 15 minutes of baking, you may need to cover lightly with a sheet of foil to prevent over-browning.
Allow bread to cool completely in pan on a wire rack. Remove bread from pan using the parchment 'handles'. Slice and serve.
Store in an airtight container in the refrigerator for 2-3 days.