• Preheat oven to 350°F (180°C). Line a 9 x 5-inch loaf pan with parchment paper. Slightly oil paper with oil spray. Set aside.
• In a large bowl, mash the bananas with a potato masher or forks until smooth, with only a few bits and pieces of banana left. Measure the exact amount required by the recipe, packing the mashed bananas in measuring cups or using a kitchen scale.
• Return to the mixing bowl and beat in egg and vanilla if used.
• Use a silicone spatula to stir in flour, sugar, cinnamon, and salt, if used. The batter should be quite thick, and that's normal.
• Pour the batter into the prepared loaf pan and bake the bread on the center rack for 40-50 minutes or until golden brown on top and a pick inserted in the center of the bread comes out clean.
• Cool down for 5 minutes in the loaf pan, then transfer to a cooling rack to completely cool down.

Storage

• Slice after 3 hours into 12 slices and store for up to 4 days in the fridge in a sealed cake box. Freeze in airtight containers for up to 1 month. Thaw it at room temperature the day before.