Preheat oven to 350 degrees.
Place ribs in a single layer in a shallow baking dish, dust lightly with salt and pepper, and bake until halfway done, approximately 30 minutes.
While the ribs are baking, combine the rest of the ingredients in a medium saucepan and bring to a boil. Reduce heat to low and cook until cranberries pop.
Spoon the cranberry mixture into a blender, and carefully blend in small batches until all the sauce has been pureed. (You can also use a stick or immersion blender to puree the sauce.) Return the sauce to a pan over medium heat and allow to simmer and thicken, about 20 minutes, stirring frequently.
Drain any juices from the partially baked ribs. Pour sauce over ribs and bake until pork is no longer pink, about 15 minutes.