Cream butter and sugar until light and fluffy. Beat in egg yolks all at once. Add vanilla. Sift dry ingredients together. Set aside 1 cup of the dry ingredients. Add the remaining flour mixture and the milk in small portions, alternately, mixing well with each addition, starting and ending with an addition of the dry ingredients. Mix together, the reserved flour and the nuts, and stir into the batter, mixing just until blended. Beat the egg whites until stiff, but not dry. Fold them into the batter.
Bake in a 9x5 greased and floured loaf pan, or 3 litre mold at 180ºC about 50-60 minutes, or until done.
Frost with your favorite icing.