1. Cook first 2 ingredients in a 3-qt. saucepan over medium heat, stirring occasionally, 10 minutes or until cider is reduced to 1/4 cup. Remove from heat, and cool completely (about 20 minutes).
2. Transfer cider mixture to a bowl, discarding cinnamon stick. Whisk in vinegar and next 6 ingredients. Add oil in a slow, steady stream, whisking constantly until smooth.