Preheat your oven to 350 F (180 C) for conventional oven. For convection oven, please lower the temperature by 20 degrees. I use a 8 1/2 x 4 1/2 inches loaf pan. I sprayed with non-stick spray and line the bottom with parchment paper for easier removal later
Coat the walnuts with a tablespoon of all-purpose flour and then shake off excess flour
Prepare the batter:
Mash the ripen bananas with a fork. I like to be able to bite into tiny pieces of bananas, but if you want it really smooth, you can use a blender or immersion blender to puree them
Add the brown sugar to the bananas and keep whisking and the sugar will dissolve and the mixture will turn watery, that’s normal. Add the egg and whisk again to combine. Add the mayo and vanilla extract and whisk to combine
Sift in flour, baking powder, ground cinnamon (if using) and salt. Use a spatula to combine. Fold in the coated walnut. As long as you don’t see any pockets of flour, you are done mixing
Pour this into the prepared loaf pan. Tap the pan on the counter a few times to pop any large bubbles. Arrange few slices of bananas on top if you like. Sprinkle some chopped walnuts
Baking:
Bake in the preheated oven for 50 minutes or until cake tester inserted comes out clean with a few crumbs are okay, as long as it's not wet. You can start checking for doneness at 30 minutes. Every oven can be different
Cool in the pan for 15 minutes and then remove from the pan to a cooling rack and let it cools down completely before slicing
Serving:
The bread tastes better the next day if you can wait
How to store:
Once the bread has cooled down completely, wrap with a plastic wrap and put in air-tight container or zipper bag and it can be stored at room temperature for 3-4 days if it's not humid where you are. If it is humid, you need to keep it in the fridge. Keep in mind that the longer you keep in the fridge, the drier it gets
I recommend freezing the leftover. Banana bread freezes well. Simply wrap it well with plastic wrap and put in a freezer bag, push all the air out and seal. It can be kept frozen for one month. Simply thaw at room temperature before serving