In the jar of a blender, add the sugar, vanilla extract, 1 tablespoons orange zest, salt, orange juice and lemon juice. Pulse until the sugar is dissolved, about 30 seconds. Transfer the mixture to a mixing bowl and whisk in the milk. Cover the bowl with plastic wrap and place it in the refrigerator until very cold, about 2 hours.
Pour the mixture into a an ice cream maker and proceed according to the directions of your ice cream maker, or until it reaches the consistency of soft serve. Add the reserved 1 tablespoon orange zest.
Transfer the sherbet to a freezer safe container and place in the freezer until very firm, about 3-4 hours or ideally overnight.
Serve it in a bowl, in a cone, or my favorite way, in a glass with orange cream soda poured over it. Yum.