Step 1Rinse and drain the cranberries, discarding any mushy berries.
Step 2In a large saucepan, combine the water and cranberry juice and bring to a boil. Add the cranberries. Cook over medium heat until most of the berries pop and the berries soften, 5 to 10 minutes.
Step 3Remove the mixture to a food processor and pulse until a thick puree forms.
Step 4Return the cranberry puree to the pan and stir in the pectin. Bring the mixture back to a boil, then stir in the sugar. Boil for an additional two minutes, then remove from heat.
Step 5Pour the cranberry sauce into a gratin or glass dish and refrigerate until set, at least 3 to 4 hours.