Preheat oven to 350ºF (176ºC), and lightly grease a loaf pan.
In a large mixing bowl, lightly beat the flax eggs with maple syrup until combined.
Whisk in the oil, mashed banana, and mix until smooth.
Stir in the flour, baking powder & soda, and cinnamon. Fold in the chocolate and nuts, mix until just combined.
Pour the batter into the prepared loaf pan, spreading it out evenly.
If you want add sliced banana, chocolate chips on top.
Bake for 40-50 minutes, or until a toothpick inserted into the center comes out clean.
Remove the loaf pan from the oven and let it cool in the pan for about 10 minutes before transferring it to a cooling rack to cool completely.
Serve with peanut butter, raspberry chia jam, or maple syrup.