Cut the racks into 2-rib pieces, season with salt and pepper and put into a slow cooker.
In a bowl, mix together the preserves, ketchup, mustard, soy sauce, garlic, chipotles, ginger and hot sauce. Pour the mixture over the ribs and cover. Cook on low for 6 to 8 hours or high for 3 to 4 hours.
When the ribs are cooked, preheat the oven to 375 degrees F. Line a baking sheet with foil.
Carefully remove the ribs from the slow cooker and place them in a single layer on the prepared baking sheet. Skim the fat from the juices and transfer the juices to a pan. Place the pan on medium-high heat and bring to a simmer.
Mix the cornstarch and 3 tablespoons water in a small bowl to create a slurry. Stir the slurry into the juices in the pan and cook until the desired thickness.
Brush the ribs with the sauce and bake, brushing with more sauce every 10 to 15 minutes, until the ribs are glazed and sticky, about 45 minutes. Serve with extra sauce.