Grease and flour or line a 9½ x 5¼ x 2¾ inch loaf pan.
Cream butter and sugar.
Add the egg.
Now stir in the bran and vanilla and mix thoroughly. Set aside.
Combine buttermilk and bananas in a medium bowl.
Sift the flour, baking powder and salt together.
Add the sifted dry ingredients alternately with the buttermilk and bananas.
Mix thoroughly.
Stir in the nuts.
Transfer the mixture to the lined pan.
The bread normally takes between 45 and 50 minutes to cook but check after 35 minutes as oven temperatures really can vary. The bread is done when a skewer inserted in the center comes out clean.
Allow to cool completely before slicing.
The bread will keep for two or three days in a sealed container or wrapped in aluminum foil.
Notes
Adapted from The Better Homes and Gardens New Cookbook