- 4 lb bone-in, center-cut pork loin
- Salt and freshly cracked black pepper
- 1 tbsp olive oil
- 1 medium yellow onion, cut into ¼-inch slices from root to tip
- 1 medium fennel bulb, fronds reserved for garnish, bulb cored and cut into ¼-inch slices from root to stalk
- 1 Granny Smith apple, quartered, cored and cut into ¼-inch slice
- 2 to 3 garlic cloves, thinly sliced
- 2 sprigs each of rosemary, thyme, and sage
- 1 cup dry white wine (like sauvignon blanc)
- ¾ cup apple-cider vinegar
- Season pork loin generously with salt and pepper; let sit for 15-20 minutes. Set the oven rack to the middle position and preheat to 400.
- Heat a large, heavy bottom skillet over medium heat; add in oil and pork loin, fat side down. Brown loin on all sides (including the ends), 6-8 minutes in total.
- Remove pork loin to a plate, pouring off all but 1 tbsp of fat. Add onion, fennel, apple, garlic, and herbs and stir. Once onions and fennel begin to brown, add wine, scraping up browned bits from bottom of pan with a wooden spoon. Add in vinegar and nestle the pork, fat side up, into pan. Insert an oven-safe thermometer into the center of loin. Place roast into oven, and set the thermometer to go off at 145°. (It should take 75–90 minutes.)
- Once cooked, place roast on a cutting board and loosely tent with foil; allow meat to rest for 20 minutes. Discard herb sprigs before serving.