In a medium saucepan, combine cranberries, orange zest, cinnamon, orange juice and brown sugar. Add enough water to cover, and bring to a boil over high heat. Immediately reduce heat and simmer about 1 hour or until sauce has thicklened. Tast for sweetness and adjust with additional sugar, if necessary. You cannot overcook so continue cooking until you have a good, thick consistency. Let mixture cool, then refrigerate in a covered container.
