Add the fresh cranberries, orange juice, and sugar to a saucepan and bring to a boil.
Simmer the cranberries for 10 to 15 minutes until most of them pop open.
Serve warm or place in a heat-safe bowl and then store in the fridge. (The sauce will be thin at first but will thicken once it cools.)
Garnish with orange zest. (You can also stir a little orange zest into the sauce for more orange flavor.)
Notes
Add a few dashes of cinnamon and/or nutmeg for more flavor.
Garnish with sugared cranberries for a festive look.
To make just a few sugared cranberries to garnish your sauce, just scoop out a few cranberries just after you have added them to the pot and before they have popped open or cracked. Roll them in some granulated sugar to make them pretty and sparkly. Set them aside for later to garnish.