01 - Preheat the oven to 350°F. Grease a 9x5-inch loaf pan or line with parchment paper.
02 - In a large bowl, mash the bananas until smooth. Add melted butter, eggs, and vanilla extract, stirring until well incorporated.
03 - In a separate bowl, whisk together the flour, granulated sugar, baking soda, and salt until evenly blended.
04 - Add the dry mixture to the wet mixture, stirring gently just until combined to avoid overmixing.
05 - Fold in the diced strawberries and, if desired, walnuts or pecans. Mix gently to distribute evenly.
06 - Transfer the batter to the prepared loaf pan and spread evenly. Bake for 50 to 55 minutes, or until a toothpick inserted into the center emerges clean.
07 - Cool in the pan for 10 minutes. Remove to a wire rack and allow to cool completely before slicing.