Preheat the oven to 350 degrees. Line a muffin pan with paper cupcake liners.In a large bowl, combine the oat flour, almond meal, baking powder, baking soda, and salt. Whisk together and set aside.In a separate bowl, mash the bananas thoroughly, then add the sugar and stir. Add the oil, water, vanilla extract, and vinegar. Stir to combine.Add the dry ingredients to the wet ingredients and stir until combined.Add the chocolate chips and mix together.Pour the batter into the prepared muffin pan.Bake at 350 degrees for 18-20 minutes. These don't rise very high, and that's okay! They are very moist and rich - not a lightweight muffin.