Preheat your oven to 350°F (175°C) and line a muffin tin with paper liners or lightly grease it to prevent sticking.
In a blender or food processor, combine the bananas, nut butter, eggs, and vanilla extract. Blend until you get a smooth mixture.
Add the chocolate protein powder, gluten-free oats, cacao powder, coconut sugar, baking soda, and baking powder to the blender. Blend again until all ingredients are well incorporated.
Finally, add the apple cider vinegar and pulse a few times to mix it into the batter.
Divide the batter evenly among the muffin cups, filling each about ¾ of the way full and then dropping some chocolate chips into each one.
Bake for 18-20 minutes, or until a toothpick inserted into the center of a muffin comes out clean.
Allow the muffins to cool in the pan for about 5 minutes, then transfer them to a wire rack to cool completely.