Drain pineapple, reserving 1 tablespoon juice. In a microwave-safe bowl, combine the pineapple, sugar, cinnamon and reserved juice. Microwave on high for 1-1/2 to 2 minutes or until mixture boils, stirring every 30 seconds. Cover and refrigerate for 1 hour.
Place 1/4 cup sherbet in two dessert dishes; top each with about 2 tablespoons pineapple mixture and 2 tablespoons granola. Cover and freeze for 30 minutes.
Repeat layers. Cover and freeze until firm, about 2 hours. Remove from the freezer 10 minutes before serving.