2/3 c. butter, cold
4 c. confectioners' sugar
1 tsp. vanilla
2-3 tbsp. cold milk

Beat butter several minutes until creamy. Add vanilla. Beat until blended. Add sugar about 1/2 cup at a time. Add milk a little at a time, mixing well after each addition. To get a very white icing, use vegetable shortening instead of butter and add some butter flavoring.