Preheat oven to 325F (163C) and spray a loaf pan with non-stick cooking spray.
Mix bananas, yogurt, coconut sugar, and vanilla until combined.
3 medium ripe bananas, mashed, ¼ cup non-fat Greek yogurt, ½ cup coconut sugar, 1 teaspoon vanilla extract
Add coconut oil and egg. Mix well.
¼ cup coconut oil, melted, 1 whole large egg
Add oat flour, whey protein, baking soda, and cinnamon. Mix well.
1 cup oat flour, ¾ cup unflavored whey protein powder, 1 teaspoon baking soda, 1 teaspoon ground cinnamon
Fold in chopped nuts and pour into pan.
⅓ cup chopped nuts
Bake for 45-50 minutes or until a toothpick inserted comes out clean.
Let cool in pan for 10 minutes, then remove from pan and let cool completely.
Slice and enjoy! Store refrigerated or frozen.