In a medium saucepan, boil 1 cup sugar and 1/2 cup water; about 2 minutes.
Lower heat to a simmer. Add in washed cranberries, saving 1/3 cup fresh cranberries for later.
Simmer cranberries until berries are soft and most have burst about 10 minutes.
Stir in salt. Stir in vanilla extract if using.
Remove from heat and stir in 1/4 cup water.
Allow mixture to cool for 15 minutes.
Cover and refrigerate until ready to serve. Cranberry sauce will thicken as it cools.
Additional stir-ins can include a pinch of cinnamon, orange zest, lemon juice, or honey.
This recipe can be stored in an air-tight container in the refrigerator for up to 1 month or stored in the freezer for 8-10 months.