In a greased 5- or 6-qt. slow cooker, combine bread and apples. In a large bowl, whisk eggs, milk, cream, sugar, cinnamon, vanilla and salt. Pour over bread mixture and stir to combine; gently press bread down into milk mixture. Cook, covered, on low until a knife inserted in the center comes out clean, 3-4 hours., Meanwhile, combine caramel syrup ingredients in a small saucepan. Cook and stir over medium heat until smooth and heated through. Serve warm with French toast.