Prosciutto-Wrapped Pork Loin with Roasted Apples

Drain apples, discarding soaking liquid.

Finely chop mushrooms and apples, combine in a small bowl, and set mushroom and apple mixture aside.

Meanwhile, blanch kale in boiling salted water just until wilted, about 1 minute.

Using tongs, transfer kale to a rimmed baking sheet.

Refrigerate until cool.

Remove any large, tough ribs.

Melt butter in a large 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, and rosemary; cook for 1 minute.

Add brandy and cook until liquid is absorbed, about 1 minute.

Stir in 2 teaspoons salt and 1/2 teaspoon pepper.

Transfer mixture to a bowl and let cool completely.

Add ground pork and stir to combine well.

To butterfly, put pork loin on a work surface with short end facing you.

Holding a long, thin sharp knife parallel to work surface and beginning along one long side, cut 1/2" above underside of roast.

Continue slicing inward, pulling back the meat with your free hand and unrolling 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 1/2 teaspoon pepper.

Place kale leaves on top of loin in an even layer, overlapping as needed and leaving a 1" border.

Spread filling on top of kale.

Roll pork into a tight cylinder.

Wrap one layer of prosciutto around roast.

Tie roast securely with kitchen twine in 1" intervals.

Tuck rosemary sprigs under twine, spacing apart.

DO AHEAD: Pork roast can be made 1 day ahead.

Cover and chill.

Let stand at room temperature for 1 hour before continuing.

Preheat oven to 400°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 1/2 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°F (it will be cooked medium but still slightly pink), about 1 hour 40 minutes.

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, scraping bottom of pan to release any browned 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 sliced pork.