Preheat oven to 350 degrees F (175 degrees C). Lightly grease an 8x4 inch loaf pan.
In a large bowl, cream together butter and sugar. Beat in the egg and mashed bananas. Mix in flour, baking soda and salt just until combined. Pour into prepared loaf pan.
Bake in preheated oven for 1 hour. If top begins to brown too quickly, decrease heat slightly. Center should be soft and chewy, while the outside, crisp and crunchy.
