In a medium saucepan, bring sugar, water, orange zest, orange juice, and salt to boil. Stir occasionally to dissolve the sugar.
Stir in cranberries. Simmer until slightly thickened and the berries begin to pop, about 10 minutes. Remove from heat and cool to room temperature or chill.
Orange zest and juice: Zest the orange first, then juice it for the sauce.
Cranberries: Fresh cranberries freeze really well, so stock up when you see them. If your cranberries are already frozen, no need to thaw. Just cook them straight from the freezer and add 2 minutes to the simmering time.
Yield: This recipe uses only 6 ounces cranberries to make 1 cup of sauce, enough for 2 (1/2-cup) servings or 4 (1/4-cup) servings.
Make ahead: Cool the cranberry sauce completely, then keep refrigerated for up to 3 days.
Freezer:Cooled sauce can be frozen up to 3 months. Thaw overnight in the refrigerator before serving.