1. In a medium saucepan, heat the sugar with 1/2 cup (125ml) water then add the cranberries and a pinch of salt.
2. Cover, and cook at a low boil for about 10 minutes, or until the cranberries are completely softened.
3. Remove from heat and let the cranberries sit until room temperature, covered.
4. Once the cranberries have cooled, puree the cranberries with any liquid and the orange juice, 1/4 cup water (60ml), and the orange-flavored liqueur, if using.
5. Chill thoroughly, then freeze in your ice cream maker according to the manufacturer’s instructions.