Preheat the oven to 350 degrees F (180 degrees C).

In a small bowl, mix 1 tablespoon of ground flaxseed with 3 tablespoons of water. Set aside for 5 minutes, this creates a flax egg.

In a large cup, stir together 1 cup of soy milk and 1 teaspoon of apple cider vinegar. Set aside for 5 minutes, this creates the vegan buttermilk.

To a large bowl, whisk together 2 cups of oat flour, 1/2 cup of almond flour, 1/2 cup of vegan protein powder, 1/4 cup of cocoa powder, 1 teaspoon of baking powder, and a pinch of salt.

In a separate medium bowl, mash 1 ripe banana with a fork. Then mix in 1/2 cup of maple syrup, 1/2 cup of melted coconut oil, 1 teaspoon of vanilla extract, and 1 cup of vegan buttermilk.

Pour the wet ingredients bowl into the dry ingredients bowl, add the flax egg, and gently mix the batter until combined.

Line the muffin pan with liners or use a nonstick silicone muffin pan. Pour about 1/3 cup of batter into each mold. Sprinkle chocolate chips on top and bake for 35-40 minutes. Stick a knife or toothpick to check it's fully baked.

Let the muffins cool for 10 minutes in the pan and enjoy!