Preheat your oven to 350° F. Grease a 9-by-5-in loaf pan and set aside.
In a large bowl, mash your bananas.
Add the eggs, oat milk, coconut oil, and vanilla extract. Whisk until combined, do not over-mix.
In a medium bowl, whisk together the pancake mix, protein powder, light brown sugar, baking soda, salt, and ground cinnamon.
Add the dry ingredients into the wet and mix just until combined and a smooth batter has formed. Fold in the walnuts.
Pour the batter into the prepared loaf pan. Smoothing out the top.
In a small bowl, combine the granulated sugar and ground cinnamon.
Sprinkle cinnamon sugar over the batter, making sure all the surface is covered. *Tip: Press the cinnamon sugar into the batter for best results.
Bake for 45- 50 minutes, or until a toothpick inserted into the center comes out clean.
Allow the bread to cool completely before slicing.