How to Make It
In a large skillet, heat 2 tablespoons of the olive oil. Add the onion and garlic and cook over moderately high heat, stirring, until soft and light golden, about 3 minutes. Stir in the diced apples and 1/4 cup of the apple cider vinegar and boil over moderately high heat until the liquid is reduced by half, about 2 minutes. Transfer to a large bowl and stir in the toasted bread cubes along with the pumpkin seeds and parsley. Season the stuffing with salt and pepper.
Using a sharp knife, score the pork skin at 1/4-inch intervals. Lay the pork loin butterflied side up on a work surface and season with salt and pepper. Spread the stuffing over the pork loin, then roll up the meat, leaving the seam on top. Drape the pork skin over the seam. Using kitchen twine, tightly tie the loin at 1-inch intervals. Season with salt and pepper, wrap in plastic and refrigerate for at least 1 hour or up to 24 hours.
Preheat the oven to 475°. In a large bowl, toss the Lady apples with the remaining 2 tablespoons each of cider vinegar and olive oil.
Unwrap the pork and transfer skin side up to a rimmed baking sheet. Roast for 20 minutes, until the skin is browned and bubbly. Reduce the oven temperature to 325° and roast for 25 minutes more. Scatter the Lady apples around the pork and scrape any liquid from the bowl over them. Continue to roast the pork for about 20 minutes longer, until an instant-read thermometer inserted in the center of the meat registers 140°.
Transfer the pork to a cutting board and set the apples on a platter. Scrape the pan drippings into a small bowl. Let the pork rest for 15 minutes, then discard the strings. Thickly slice the pork and transfer to the platter. Drizzle with the pan drippings and pumpkin seed oil and serve.