01 - Preheat oven to 350°F. Grease and flour a 9x5-inch loaf pan or line with parchment paper.
02 - Whisk mashed bananas, eggs, oil or butter, yogurt or sour cream, sugar, and vanilla extract in a large bowl until thoroughly combined.
03 - Sift together flour, baking soda, salt, and cinnamon in a separate bowl.
04 - Gently fold dry ingredients into wet mixture, mixing just until incorporated. Avoid overmixing to prevent dense texture.
05 - Stir in walnuts, pecans, or chocolate chips if desired.
06 - Pour batter into prepared loaf pan, smooth top, and bake for 50-60 minutes until toothpick inserted in center comes out clean or with few moist crumbs.
07 - Let cool in pan for 10 minutes, then transfer to wire rack to cool completely before slicing.