Preheat the oven to 350°F and grease and flour a bread loaf pan. Lightly roast walnuts on a skillet, then coarsely chop and cool.

In a mixing bowl, cream together the softened butter and sugar.

Mash bananas to a chunky applesauce consistency and add them to the batter along with the eggs, mixing until blended.

In a separate bowl, whisk together flour, baking soda, and salt, then add this mixture to the batter.

Add vanilla extract and mix in the chopped walnuts and raisins. Pour the batter into the prepared loaf pan and bake at 350°F for 55-60 minutes, or until a toothpick inserted into the center comes out clean. Let the banana bread rest for 10 minutes before transferring to a wire rack to cool.