1. Preheat oven to 325 deg F.
  2. Sift flour. To the last cup of flour, add baking powder and set aside.
  3. Cream butter and sugar until smooth or brown-colored.
  4. Add beaten egg yolk, mix thoroughly.
  5. Add the flour alternately with the milk; end with last cup sifted with baking powder.
  6. Beat egg whites with cup sugar and fold to the egg yolk mixture (in mixing and with mixing by hand)
  7. Pour into a well-greased 10" tube pan or loaf pan, lined with wax paper. (NOTE: For butter cakes, push butter slightly to the side of pan before baking. When pouring mixture into pan, do so as fast as possible.)