In 2 quart glass bowl, Microwave margarine for 1 minute. Stir in vanilla pudding and milk. Microwav, uncovered until boiling, about 3 minutes, stirring occasionally. Cook for 1 minute more, stirring every 15 seconds. Add vanilla. Beat in confectioner's sugar. Stir in chopped nuts or candied cherries. Pour into buttered 10x6x2" baking dish. Top with nut halves, if desired. Chill. Cut in 1" squares. Store in refrigerator.