- 1 oz. (1 cup) dried whole porcini mushrooms
- 2 oz. (3/4 cup) dried apples
- 1 lb. kale, bottom stems trimmed
- 2 teaspoons kosher salt plus more
- 2 tablespoons (1/4 stick) unsalted butter
- 1 cup minced onion
- 1 teaspoon minced garlic
- 1½ teaspoon dried thyme
- 1½ teaspoon dried rosemary
- 2 tablespoons brandy or Calvados
- ½ teaspoons freshly ground black pepper
- 1 lb. ground pork
1 (trimmed) 2½-3lb pork loin
1 teaspoon kosher salt plus more for seasoning
½ teaspoon freshly ground black pepper plus more for seasoning
3 oz. thinly sliced prosciutto
5 springs rosemary
4 medium apples (such as Granny Smith or Fuji), quartered, or 8 small apples, halved
2 tablespoons extra-virgin olive oil
1 cup dry hard cider
½ cup low-salt chicken stock
Place dried mushrooms and dried apples in separate small bowls. Add 1 cup boiling water to each bowl. Let mushrooms and apples soak until very soft, about 30 minutes. Strain mushrooms, reserving soaking liquid (about ¾ cup). Cover and chill liquid. Drain apples. Drain apples, discard soaking liquid. Finely chop mushrooms and apples, combine in a small bowl, and set mushroom and apple mixture aside.
Melt butter in a skillet over medium heat. Add onion; cook, stirring often, until soft and lightly golden, about 8 minutes. Add mushrooms and apples; cook stirring occasionally, until flavors meld, about 5 minutes. Stir in garlic, thyme, rosemary; cook for 1 minute. Add brandy and cook until liquid is absorbed, about 1 minute. Stir in 2 teaspoons salt and ½ teaspoon pepper. Transfer mixture to a bowl and let cool. Add ground pork and stir to combine.
Pork: Ask your butcher to trim and butterfly a pork loin for you. Unroll the roast like a carpet, until the entire loin is flat. Cover with a sheet of plastic wrap. Using a meat mallet, pound to an even thickness.
Uncover pork. Season with 1 teaspoon salt and ½ teaspoon pepper. Place kale leaves on top of loin in an even layer overlapping as needed and leaving 1 inch border. Spread filling on top of kale.
Roll pork into a tight cylinder. Warp one layer of prosciutto around roast. Tie roast securely with kitchen twine in 1 inch intervals. Tuck rosemary springs under twine, spacing apart. DO AHEAD: Pork roast can be assembled 1 day ahead. Cover and chill. Let stand at room temperature for 1 hour before continuing.
Preheat oven to 400 degrees F. Place apples in a roasting pan. Melt 1 tablespoon butter with oil in a large skillet. Brown pork on all sides, about 5 minutes total, then set on top of apples in pan. Add cider and ½ cup water to skillet and bring to a boil, scraping up browned bits. Pour mixture into roasting pan. Roast pork until an instant-read thermometer inserted into center of loin registers 140 degrees (it will be cooked medium but still slightly pink), about 1 hour and 40 minutes (check for doneness at 1h30). Let roast rest for at least 20 minutes and up to 2 hours.
Put roast on a platter. Reserve apples from roasting pan; spoon off fat from juices in pan. Place pan on top of stove over medium-high heat. Add chicken stock. Pour in reserved mushroom liquid, leaving any sediment behind, and cook, scrapping bottom of pan to release any brown bits, until slightly thickened, about 5 minutes. Whisk in remaining 2 tablespoons butter and season to taste with salt and pepper. Strain sauce; slice pork. Serve sauce and apples alongside pork.