Martha Stewart's Banana Bread

1/4 Pound (1 stick butter), room temp
1 c sugar
2 eggs
1 1/2 c flour
1 t baking soda
1 t salt
1 c mashed very ripe bananas
1/2 c sour cream
1 t vanilla extract
1/2 c chopped walnuts or pecans

Preheat oven to 350°F, butter 9X5X3" loaf pan. With an electric mixer, cream the butter and sugar until light and fluffy. Add the eggs beating well. Sift (yeah right) the dry ingredients together and combine with the butter mixture. Blend well. Add the bananas, sour cream, and vanilla. Stir well. Stir in the nuts and pour into the pan. Bake 1 hour until a cake tester comes out clean. Turn out onto a rack to cool.