Preheat oven to 350 degrees (175 degrees C). Ovens may vary with temperature.

Spray muffin pan with a non-stick spray, or use paper liners.

In a medium bowl combine AP flour, oat flour, wheat bran, flax seed meal, baking powder, baking soda, and salt. Using a fork stir a few times so the ingredients are mixed evenly. Set aside.

In a large mixing bowl add the bananas and mash them, leaving a few chunky pieces of the banana. Then add the brown sugar, eggs, and melted butter. Mix on a low-med speed until well combined.

Next, add the flour mixture into the mixing bowl with the wet ingredients on low to medium speed; adding a small amount at a time until smooth and well mixed.

This is when you will fold in the coconut, and walnuts if desired. Making sure it is well mixed, and even throughout the batter.

Fill the muffins 3/4 of the way, and bake 25-30 minutes. They will be done when edges and top are slightly browned.