01 - Preheat the oven to 350°F. Grease and flour a 9x5-inch loaf pan or line it with parchment paper.
02 - In a large bowl, whisk together the flour, sugar, baking soda, salt, and cinnamon if using.
03 - In a separate bowl, blend the mashed bananas, melted butter, milk, eggs, and vanilla extract until smooth.
04 - Pour the wet ingredients into the dry mixture and stir gently until just combined, avoiding overmixing.
05 - Fold in the chocolate chips and chopped walnuts evenly.
06 - Pour the batter into the prepared loaf pan and smooth the surface.
07 - Bake for 50 to 60 minutes or until a toothpick inserted into the center comes out clean, allowing for a few moist crumbs but no wet batter.
08 - Let the bread cool in the pan for 10 minutes before transferring it to a wire rack to cool completely.