Pork Cheeks with Pickled Onions, Mustard Seeds, and Daikon

Fill a small saucepan with 2 cups water; bring to a boil over medium-high. Add onion and salt; cook, stirring occasionally, until onion has softened, 2 to 3 minutes. Drain through a fine wire-mesh strainer. Transfer drained onion to a medium-size heatproof bowl; set aside. Do not wipe saucepan clean.

Add sugar, vinegar, and remaining 2/3 cup water to saucepan; bring to a boil over medium high. Add mustard seeds; cook, stirring occasionally, until sugar has dissolved, about 2 minutes. Pour mixture over onion in bowl; let cool slightly, about 15 minutes. Cover bowl with plastic wrap. Refrigerate until onion expands slightly in liquid, at least 4 hours or up to 4 days. Combine 2 cups water, 2 teaspoons kosher salt, and pink salt in a small saucepan; bring to a boil over medium-high. Stir until salt is fully dissolved. Remove from heat. Let cool about 30 minutes.

Place pork cheeks in a large ziplock plastic bag; carefully pour salt water into bag. Seal bag, and place on a plate or rimmed baking sheet. Place in refrigerator, and let brine 2 days.

Remove pork cheeks from brine; pat with paper towels until fully dry. Discard brine in bag. Heat oil in a large skillet over medium-high. Working in 2 batches, add 5 cheeks to skillet; cook until dark brown on both sides, 8 to 10 minutes per batch. Transfer cheeks to a programmable pressure multicooker (such as Instant Pot). Do not wipe skillet clean.

Add onion, carrot, and celery to skillet; cook, stirring occasionally, until vegetables start to soften, about 5 minutes. Add wine; cook, stirring often and scraping up browned bits on bottom of skillet, until liquid is completely reduced and skillet is almost dry, about 5 minutes. Arrange vegetables over pork cheeks in multicooker. Pour remaining 5 cups water over cheeks and vegetables to submerge. Cover cooker with lid, and lock in place. Turn steam release handle to SEALING position. Select MANUAL/PRESSURE COOK setting. (Times, instructions, and settings may vary according to cooker brand or model.) Select HIGH pressure for 1 hour. (It will take 15 to 18 minutes for cooker to come up to pressure before cooking begins.) When cooking has finished, let the pressure release naturally. (Float valve will drop.) (This will take 35 to 45 minutes.) Remove lid from cooker, and let pork cheeks cool in liquid 30 minutes. Remove cooker bowl from machine; cover bowl with plastic wrap. Refrigerate until mixture has completely chilled, at least 4 hours or up to 12 hours.

Preheat oven to 180°F. Remove plastic wrap from cooker bowl. Scrape off any solidified fat from top of pork cheek mixture, and discard. Transfer cheeks to a large saucepan, reserving liquid in cooker bowl. Pour liquid in cooker bowl through a fine wire-mesh strainer over cheeks in saucepan; discard strained solids. Place saucepan on stovetop, and bring to a simmer over medium. Simmer, stirring occasionally, until cheeks are heated through, about 10 minutes. Remove cheeks from liquid, and place in a baking dish. Ladle about 2/3 cup hot liquid over cheeks in baking dish. Cover baking dish with aluminum foil, and place in preheated oven to keep warm.

Increase heat under saucepan to medium-high; cook liquid, undisturbed, until thickened, saucy, and reduced to 2/3 cup to 3/4 cup, about 20 minutes. Remove from heat. Pour through a fine wire-mesh strainer set over a medium-size heatproof bowl; set aside. Discard solids.

Place daikon in a medium bowl. Using a slotted spoon, remove pickled onion and mustard seeds from pickling liquid, and spoon over daikon. Pour 1/2 cup pickling liquid over daikon mixture; discard remaining pickling liquid. Stir in remaining 1/2 teaspoon kosher salt.

Spoon strained sauce evenly into 5 shallow bowls. Remove pork cheeks from oven; place 2 cheeks on sauce in each bowl. Using a slotted spoon, garnish each bowl with desired amount of pickled onion–daikon mixture. Serve immediately.