01 - Preheat oven to 350°F (175°C). Grease a 9x5-inch loaf pan with butter or nonstick spray.
02 - In a medium bowl, whisk together the flour, baking soda, and salt until evenly mixed.
03 - In a large bowl, beat softened butter and granulated sugar until light and fluffy.
04 - Mix in eggs one at a time, followed by the vanilla extract, beating well after each addition.
05 - Fold mashed bananas into the wet mixture until just combined.
06 - Gradually mix dry ingredients into the wet mixture until a uniform batter forms. Do not overmix.
07 - Fold in chopped walnuts if using, ensuring an even distribution.
08 - Pour batter into the prepared loaf pan and smooth the top with a spatula.
09 - Bake on the center rack for 55 to 65 minutes, or until a toothpick inserted in the center emerges clean.
10 - Cool in the pan for 10 minutes, then transfer to a wire rack to cool completely before slicing.