1Beat butter in a large bowl until fluffy. Gradually add 3 cups of the sifted confectioners' sugar, beating well. Slowly beat in the vanilla, salt, and 1/3 cup of the milk. Gradually beat in the 3 remaining cups of confectioner's sugar. Beat in additional milk (1 to 2 tablespoons) if needed, to make frosting of spreading consistency. If desired tint the frosting pink with 6 to 8 drops of red food coloring.