Preheat oven to 350 degrees.
Prepare flax egg in a small bowl and set aside.
In a high speed blender, add the oats.
Pulse until a flour forms (about 30 seconds or so).
Add the ripe bananas, almond flour, flax egg, maple syrup, peanut butter, baking soda, and sea salt.
Cover blender and blend on the lowest setting, stopping a few times to scrape down the sides with a spatula. Once the ingredients are combined, transfer to a medium bowl.
Add the walnuts and chocolate chips.
Use a cookie scoop and form 12 muffin tops (I used two cookie sheets to give them space). slice remaining banana into coins and place one on top of each muffin top.
Bake 13-15 minutes.
Store in an airtight container in the fridge for up to one week.