Bring sugar and fresh orange juice to a boil in a saucepan over medium-high heat, stirring to dissolve the sugar. You should see steady bubbling across the surface within about 2 to 3 minutes.

Add fresh cranberries and salt, then return to a boil. Reduce heat to a simmer and cook for 10 minutes, stirring occasionally, until most berries burst and the sauce looks thickened.

Remove the saucepan from the heat and stir in orange zest until evenly distributed. The zest should turn glossy in the warm sauce.

Let the sauce cool slightly for 5 minutes so the orange segments stay intact. It should be warm but not hot.

Gently fold in orange, peeled and segmented, using a light hand to avoid mashing the fruit. Stop when the segments are coated and suspended throughout.

Chill the cranberry orange sauce until serving. Refrigerate in a covered container for at least 1 hour to set the texture.