Melt 1 tsp. butter with 1 square unsweetened chocolate over warm, not boiling, water. Remove from heat and stir in 1½ to 2 tblsp. hot water. Add enough sifted confectioners sugar (about 1 c.) to make icing that spreads easily. Beat until smooth. Makes enough to ice from 3 to 4 dozen cookies, depending on size, or a 9" square pan of cookies.