4 days before you want to make this banana bread, start fermenting the bananas.
Mash bananas in a large bowl, but not too finely, and leave at room temperature, covered with a cling wrap, for 48-72 hours. After that, put into the fridge and leave for another 32 hours before using.
Place sultanas and dark rum in a saucepan and bring to a boil. Cover and set aside while preparing other ingredients.
Lightly grease a loaf pan (9 x 5 x 3 inches) and pre-heat oven to 338F.
Sift flour, baking powder, baking soda and salt in a large bowl. Stir in bran.
In a medium bowl, add melted butter, coconut oil and Alligga flaxseed oil with sugar and whisk until sugar is dissolved.
Add in eggs, fermented bananas, crushed pineapple and vanilla extract. Mix until combined.
Add in dry ingredients in a few batches. Stir until combined. The batter will be lumpy.
Fold in walnuts and sultanas.
Pour into loaf pan and top with roasted flaxseeds.
Bake for 1 to 1 1/4 hours until a skewer in the middle of the loaf comes out clean. If the loaf gets too dark during baking, you can cover with tinfoil.