Ingredients

• 1 large or 2 medium leeks, slit lengthwise, rinsed, then thinly sliced crosswise, white and pale-green parts only (about 1 cup)
• 1 cup low-sodium soy sauce
• 6 Tbs. Shaoxing or dry sherry
• 1/4 cup peeled, julienned fresh ginger (cut into 1/8 x 1/8-inch matchsticks; from a 3-inch piece)
• 2 Tbs. granulated sugar
• 1 Tbs. slivered garlic (3 medium cloves)
• 2 cinnamon sticks
• 1 star anise pod
• 4 lb. boneless pork shoulder (also called butt), trimmed and cut into 4 large pieces
• 2 cups jarred roasted peeled chestnuts
• 2 Tbs. plain rice vinegar, more to taste
• Cooked medium-grain white rice or udon noodles, for serving
• Thinly sliced scallions, for garnish