Preheat your oven to 350°F (175°C). Lightly grease your loaf pan with butter or line it with parchment paper to prevent sticking.
Peel your ripe bananas and place them in a large mixing bowl. Mash them with a fork or potato masher until smooth with some lumps remaining.
Add melted butter to the mashed bananas and stir to combine. Mix in sugar, beaten egg, and vanilla extract until well incorporated.
In a separate bowl, whisk together all-purpose flour, baking soda, and a pinch of salt to evenly distribute ingredients.
Gradually add the dry ingredients to the wet banana mixture, stirring gently until just combined. Avoid overmixing to keep the bread tender.
Fold in the chopped walnuts evenly into the batter for added crunch and flavor.
Pour the batter into the prepared loaf pan and smooth the top. Bake for about 60 minutes, or until a toothpick inserted in the center comes out clean or with a few moist crumbs.
Let the bread cool in the pan for 10 minutes, then transfer to a cooling rack. Slice and enjoy once cooled.