I tried this recipe this morning and loved it.  You may want to add more sugar if you really have a sweet tooth. If not, it is perfect as it is.

Ingredients

• 1/2 cup butter, softened  
• 1 cup white sugar
• 2 eggs
• 1 1/2 cups mashed banana
• 2 cups all-purpose flour
• 1 teaspoon baking soda
• walnuts

Directions

1. Preheat oven to 350 degrees F (175 degrees C). Grease and flour one 9×5 inch pan.
2. Cream margarine and sugar until smooth. Beat in eggs, then bananas. Add flour and soda, stirring just until combined. Add walnuts.
3. Pour into prepared pan and bake at 350 degrees F (175 degrees C) for about 1 hour (or till toothpick comes out clean). Remove from pan and let cool, store in refrigerator or freeze.