Preheat oven to 350°
In a large bowl, add all the dry ingredients (flour, baking soda, cinnamon, protein powder, salt).
In another large bowl, add the bananas and mash them with a fork. Add the egg, coconut oil, syrup, vanilla extract and whisk.
Add the dry ingredients to the wet ingredients. Whisk.
Add 1/2 cup chocolate chips and the walnuts and mix using a rubber spatula.
Pour the batter evenly into a muffin pan. Top with remaining chocolate chips and bake for about 18-20 minutes depending on your oven or until you insert a toothpick in the center and the pick comes out clean.
Allow to cool or at least 15 minutes and cool.