For brining pork
- 8 cups water
- 1/3 cup kosher salt
- 2 tablespoons maple syrup (medium or amber)
- 1/2 teaspoon crushed black peppercorns
- 2 sprigs fresh sage
- 1 large garlic clove, smashed
- 1 Turkish or 1/2 California bay leaf
- 1 (4- to 4 1/2-lb) boneless pork loin roast, trimmed
- 3 garlic cloves, finely chopped
- 2 tablespoons finely chopped fresh sage
- 3 tablespoons maple syrup (medium or amber)
- 16 bacon slices (about 1 lb)
- 1 tablespoon cider vinegar
- 1/2 teaspoon cornstarch
- 1 teaspoon water
Combine all brining ingredients except pork loin in a 3- to 4-quart saucepan and heat over high heat, stirring, until salt is dissolved. Pour brine into a deep 4- to 5-quart pot; cool to room temperature, uncovered, about 2 hours.
Add pork to brine, making sure it is completely covered by brine, and marinate, covered and chilled, 8 to 24 hours.
Put oven rack in middle position and preheat oven to 350°F.
Pat pork dry (discard brine) and remove any strings, then transfer to a roasting pan. Stir together garlic, sage, and 1 tablespoon syrup in a small bowl and rub all over pork. Lay bacon slices crosswise over loin, overlapping slightly, and tuck ends of bacon underneath loin.
Roast pork until thermometer registers 140°F, about 1 1/4 hours. Stir together 1 tablespoon syrup and vinegar until combined. Brush vinegar mixture over bacon slices and continue to roast pork until thermometer registers 150°F, about 10 minutes more. Remove from oven and let stand in pan 15 minutes. Transfer roast to a cutting board with a lip, reserving juices in pan, and let roast stand, uncovered, while making sauce.
Skim fat from pan juices and discard, then transfer jus to a small saucepan and bring to a simmer. Stir together cornstarch and water and whisk into jus. Simmer, stirring, until slightly thickened, about 1 minute. Remove from heat and stir in remaining tablespoon syrup. Serve pork with sauce.