The night before, mix starter, oil, honey, and flour to a large mixing bowl. This will be a stiff dough. Mix well, cover and allow to ferment for 8-24 hours.
The next day, preheat the oven to 350 degrees F.
In a blender or food processor add the eggs, bananas, and vanilla and process until smooth.
The fermented dough will be stiff, so, take your hands and break it up into small crumbles. Alternatively, you could pulse in a food processor or in a stand mixer.
Add the banana mixture, baking soda, baking powder, cinnamon, and salt to the dough.
Mix well. You can do this with a potato masher or in a stand mixer/food processor.
Prepare a loaf pan by greasing and dusting with a little flour.
Bake in preheated oven for 1 hour or until a toothpick comes out clean.
Carefully remove the loaf and place on a cooling rack.
Allow to cool completely before slicing.
Store in an airtight container for 3-4 days or freeze for up to 6 months.