Make a simple sugar syrup with the water and sugar and boil five minutes. Place the chocolate pieces in a large bowl and when the syrup is done boiling, add it to the chocolate. Let it sit while the chocolate melts. The less handling of the mixture will prevent the chocolate from becoming too grainy. Stir quickly to completely melt the chocolate and stir over a bowl filled with ice water to cool it down enough before chilling in the refrigerator. Stir well once more and add it to your ice cream maker and follow manufacturers' Instructions.