Preheat the oven to 350 ºF (175 °C). Butter and flour a 1-pound loaf pan, either a 9x5-inch (23x12.5x7.5 cm) loaf pan (like this Nordic Ware pan on Amazon) or for a taller loaf, use an 8.5x4.5-inch (21.5x11.5x7 cm) loaf pan (like this Oxo pan on Amazon). Line the bottom with a rectangle of parchment. Set aside.
In a large bowl, combine the mashed bananas with the sugar. Whisk in the oil.
In a separate bowl, combine the flour with the baking soda and the salt.
Fold the dry ingredients in the bowl with the wet batter and stir everything together to incorporate it and form a thick batter. Don't overmix.
Pour the batter into the prepared pan and bake for approximately 60–65 minutes or until a cake tester inserted into the centre of the bread comes out clean.
Let cool 10 minutes, then unmold onto a wire rack to cool completely.
Notes
Use the largest bananas you can find for this recipe: I used almost a pound of bananas and after peeling, I was left with roughly 375 grams of fruit, which works out to 330–375 mL (between 1⅓ and 1½ cups) of mashed banana.
Make sure the bananas are very ripe (black even).
If using frozen bananas, make sure to defrost before peeling. Place in a fine mesh sieve fitted over a bowl to strain the banana juice. Either discard the liquid OR boil it down to a very thick syrup (makes just a couple tablespoons of banana concentrate). Add this syrup to the mashed bananas and proceed with the recipe.