Scald half and half in top of double boiler set over simmering water. Add chocolate. Reduce heat so water barely simmers and cook until chocolate is melted, stirring occasionally. Remove from heat. Using electric mixer, beat eggs in medium bowl to blend. Add sugar and beat until dissolved. Slowly mix in chocolate mixture. Beat in cream. Refrigerate until well chilled.

Process chocolate mixture in ice cream maker according to manufacturer's instructions. Freeze in covered container at least 4 hours to mellow. If frozen solid, let ice cream soften slightly in refrigerator before serving. Makes about 2 quarts.