Preheat the oven to 350 degrees F and line a 9” x 5” loaf pan with parchment paper.
Mash the bananas then whisk together the mashed banana, avocado oil, vanilla extract and cider vinegar until well-combined.
In a separate bowl, stir together the flour, sugar, baking soda, ground cinnamon and sea salt until well-combined.
If adding chocolate chips and/or nuts, add them to the flour mixture and stir until they’re evenly distributed throughout the dry mixture.
Pour the dry mixture into the bowl with the wet mixture and stir until well-combined.
Transfer the banana bread batter to the parchment-lined pan and smooth it into an even layer. If you’d like, you can sprinkle more nuts and/or chocolate chips on top.
Bake on the center rack of the preheated oven for 40 to 50 minutes, or until the bread tests clean.
Allow the bread to cool for at least 30 minutes before slicing and serving.