Wash the cranberries and discard any soft or discolored ones.

Cut the ends off the orange, then cut into eight sections, leaving the peel on.

In a food processor, combine cranberries and orange sections. Pulse until the mixture is finely chopped but still has some texture.

Transfer the mixture to a bowl and stir in the granulated sugar until well combined.

Cover the bowl and refrigerate the relish for at least one hour to allow the flavors to meld together.

Serve the cranberry relish chilled as a side dish with your main course.