In a large saucepan, combine all ingredients. Cover and reduce heat. Simmer for 20 to 30 minutes.
Remove from heat and cool slightly. Mash to a thickness you like with a potato masher or fork.. Serve warm or cold.
Refrigerate leftovers within 2 hours.
When frozen or fresh cranberries are not available, substitute canned cranberry sauce for the cranberries and brown sugar. Add 1 can (14 ounces) of cranberry sauce to the saucepan after the mixture has been simmering for about 15 minutes.
For a smooth texture, puree in batches in a regular blender, using the manufacturer's directions for pureeing hot liquids.