Cream together butter, sugar, & egg yolks until creamy.
Sift dry ingredients together (flour, baking soda, salt, cinnamon & nutmeg). Alternately add the dry mixture to the creamed butter mixture as well as the milk & mashed bananas. Beat the egg whites until a stiff peak forms and fold in with a wooden spoon, (make sure you only use a wooden spoon to do this - this is KEY), next - fold in the chopped nuts also stir in with the wooden spoon.
Bake in a loaf pan that you have sprayed with olive oil or non-stick spray and dusted lightly with flour at 350° for approximately 45 minutes - insert a toothpick in the center of the loaf to ensure it is not runny, if it is - allow to bake an additional 5-10 minutes.
Cool on a wire rack and serve with cream cheese or your favorite margarine.
Note: I love to wait a day and then toast a piece in my toaster oven - it is SO good when it gets re-heated and toasty with butter on it and a cup of coffee - YUM!