Preheat oven to 350°F.
In a separate mixing bowl, mash bananas with a fork
Mix in butter, sugar , and vanilla. Stir until well combined.
flours, baking soda, salt in a large mixing bowl. Set aside.
Combine wet ingredients into dry ingredients. Stir until just combined - do not over mix.
Mix in walnuts.
Spoon batter evenly into greased muffin cups.
Bake for about 22 - 26 minutes or until muffins are golden brown.
Now insert toothpick into center and check whether it comes out clean.
Let muffins rest in pan on wire rack for 5 minutes. Remove from pan and let cool completely on rack.