This is a good wedding cake icing. While frosting cake, keep bowl covered with a damp cloth to prevent excessive evaporation. Makes enough to frost one 3 tiered wedding cake, and to decorate with garlands and flowers.
1 Cream butter or margarine. Add salt and part of the sugar gradually, blending after each addition. Add remaining sugar, alternately with the egg whites first, then with the cream; beat after each addition. Beat after each addition until smooth. Add vanilla, and blend.