Preheat oven to 350 degrees. Grease a 9x5 loaf pan and set aside.
Add in the dry ingredients and beat slowly until well combined.
Add the eggs and vanilla and beat well.
In a small bowl, use a fork to mash the bananas very well. Add the mashed bananas to the bowl and beat well.
Add the melted butter to the batter and beat until well combined.
Transfer the batter to the prepared loaf pan. Spread the top evenly.
Bake for 50 to 55 minutes or until a knife test comes mostly clean.
Store in an airtight container on the counter up to 1 week or the freezer for 3 months.
Notes
See "ingredients and subsitutions" section of the post for appropriate substituions. You may cream the butter and allulose together instead of melting the butter but it will not change the final outcome of the banana bread.