Sri Lankan–Style Black Pork Curry

Toast 15 fresh curry leaves, 18 whole cloves, 5 cardamom pods, one 4"-long Ceylon cinnamon stick, broken into small pieces, 2 Tbsp. black peppercorns, 1 Tbsp. coriander seeds, 1 tsp. cumin seeds, and 1 tsp. fennel seeds in a dry small skillet over medium-low, stirring occasionally, until fragrant, about 3 minutes. Transfer to spice mill or mortar and pestle and let cool. Grind to a fine powder. Set curry powder aside.

Place 1½ lb. skinless, boneless pork shoulder (Boston butt), cut into 1" pieces, in a medium bowl. Add ½ cup distilled white vinegar, 1 tsp. turmeric powder, and 1 Tbsp. Diamond Crystal or 1¾ tsp. Morton kosher salt; toss to coat. Cover and chill 30 minutes.

Heat ¼ cup vegetable oil in a medium Dutch oven or other heavy pot over medium-high. Cook 2 medium onions, finely chopped, 6 garlic cloves, finely grated, and one 2" piece ginger, peeled, finely grated, stirring often, until fragrant and onion is translucent, about 5 minutes. Mix in 10 fresh curry leaves, 1 lemongrass stalk, bottom third only, tough outer layers removed, lightly bruised, and reserved curry powder, then add pork along with any vinegar at the bottom of the bowl and mix well. Pour in 1½ cups water and bring to a boil. Reduce heat to low, cover pot, and simmer, stirring occasionally and adding up to ½ cup more water if needed, until pork is tender and liquid is slightly thickened, 1½–2 hours. Taste and season with more salt if needed. Fish out lemongrass; discard.

Divide pork curry among shallow bowls or plates and serve with steamed rice.