Preheat the oven to 400 degrees . In a 5-quart Dutch oven, arrange half the onions in an even layer. Top with half the potatoes, arranging in an even layer; season lightly with salt and pepper. Repeat with the remaining onions and potatoes; season. Pour in the cider.
Season the pork chops and place on top of the potatoes and onions in a single layer. Top with the parsley and rosemary sprigs.
Bake, uncovered, until the potatoes are tender, about 45 minutes. Slice the pork chops and serve with the potatoes and onions.