Preheat your oven to 350 degrees F (175 degrees C). Grease a muffin tin or line with paper liners.

In a large mixing bowl, mash the bananas with a fork or potato masher until they are smooth.

Add the chopped walnuts, applesauce, honey, egg, and vanilla extract to the bowl and mix well.

In a separate bowl, whisk together the baking soda, salt, and whole wheat flour.

Add the dry ingredients to the wet ingredients and mix until just combined.

Pour the batter into the muffin tin, filling each cup about 2/3 full.

Bake for 18-20 minutes, or until a toothpick inserted into the center of a muffin comes out clean.

Let the muffins cool for a few minutes before removing them from the tin and serving.