1. Preheat your oven to 350 F (175 C). Lightly grease and flour a 9×5-inch loaf pan, or line it with parchment paper, leaving an overhang on the sides to easily lift the bread out later.

2. In a large mixing bowl, whisk together the whole wheat flour, protein powder, baking soda, salt, and ground cinnamon. Make sure there are no lumps and the ingredients are evenly distributed.

3. In a separate medium bowl, mash the ripe bananas thoroughly with a fork until mostly smooth. Add the low-fat cottage cheese, unsweetened applesauce, maple syrup (or honey), eggs, and vanilla extract. Whisk these wet ingredients together until well combined and the cottage cheese is mostly broken down.

4. Pour the wet ingredient mixture into the bowl with the dry ingredients. Stir gently with a spatula or wooden spoon until just combined. Be careful not to overmix; a few small lumps of flour are perfectly fine and will prevent a tough bread. If using, fold in the chopped walnuts or pecans at this stage.

5. Pour the batter evenly into your prepared loaf pan. You can gently tap the pan on the counter a few times to settle the batter and remove any large air bubbles.

6. Place the loaf pan in the preheated oven and bake for 45-55 minutes. The banana bread is done when a wooden skewer or toothpick inserted into the center comes out clean or with only a few moist crumbs attached. The top should be golden brown.

7. Once baked, remove the loaf pan from the oven and let the banana bread cool in the pan for about 10-15 minutes. This allows it to set up properly. Then, carefully lift it out of the pan using the parchment paper overhang or invert it onto a wire rack to cool completely before slicing and serving.