Rinse the fresh cranberries thoroughly and pat them dry. Quarter the orange, including the peel, and remove any seeds. Chop the walnuts into small pieces if they aren’t pre-chopped.
Add the cranberries and orange quarters to your food processor. Pulse several times until the mixture is coarsely chopped but not pureed, keeping some texture.
Transfer the chopped fruit to a mixing bowl. Stir in the granulated sugar, chopped walnuts, and ground cinnamon. Mix well to combine.
Taste your relish and adjust the sugar or cinnamon to your liking, adding more for sweetness or warmth if desired.
Cover the bowl or transfer the relish to an airtight container. Refrigerate for at least 1 hour before serving to allow flavors to meld. Serve chilled.
