Preheat oven to 350 degrees F. Line a 9x5 loaf pan with parchment paper.
In a large bowl, make the flax eggs by combing the ground flaxseed and water. Stir and set aside for 5 minutes to thicken.
In a medium bowl, add the oat flour, cacao powder, protein powder, baking soda, baking powder, and salt. Whisk until combined.
In the bowl with the flax eggs, mash the ripe bananas. Then add the vanilla, avocado oil, pure maple syrup, apple cider vinegar, and milk. Whisk until well combined.
Add the dry ingredients into the bowl with the wet. Stir with a spatula until just combined. Don’t overmix! Fold in chocolate chips. Pour batter into the lined loaf pan. Top with extra chocolate chips.
Bake for 60-70 minutes, or until a toothpick inserted comes out clean. Let it cool in the pan for 15 minutes. Then transfer bread to a cooling rack to cool completely. Enjoy! Store in an airtight container on the counter for 3 days.