Preheat oven to 350 degrees F or 175 degrees C and spray a 9X5 loaf pan with non-stick cooking spray.
In a large bowl, cream butter with 1 cup sugar, using an electric hand mixer on medium speed, then add beaten eggs.
In a medium bowl, sift dry ingredients (flour, salt and baking powder) together. Then add this flour mixture to butter mixture, alternately with milk, a little bit at a time, mixing well between additions.
Finely grate 1 whole lemon into a small bowl, then add the grated rind to the batter.
Stir in walnuts.
Baking time: Pour into prepared pan and bake for 45-55 minutes or until cake tester or toothpick comes out clean.
Cool hot bread for 5 minutes in pan, then run knife (or spatula) around edge of bread pan and remove to wire rack to cool for an additional 10 minutes.
Sprinkle additional walnuts and lemon zest on top of the bread, if desired.