In a blender, combine 3 dried red chilies, 1 tablespoon of cumin seeds, 1 tablespoon of coriander seeds, 1 teaspoon of black cardamom seeds, 1 teaspoon of fenugreek seeds, 5 whole cloves, and 1 cinnamon stick, 1in / 2.5cm long.
Add 10 black peppercorns, 4 green chilies, 75ml of white wine vinegar, 2 tablespoons of brown sugar, 1 tablespoon of tamarind paste, and 2 tablespoons of ginger-garlic paste. Blend to a smooth paste.
Coat 800g of pork shoulder, cut into chunks, in the paste. Cover and marinate for at least 30 minutes.
Heat 4 tablespoons of coconut oil in a large pot over low heat. Gently fry 1 head of garlic, peeled and slivered, for about 10 minutes, until soft and lightly browned. Lift out the garlic.
Fry 1 teaspoon of mustard seeds and 20 curry leaves in the oil until the seeds pop. Add 2 chopped onions and fry until soft. Stir in 1 tablespoon of Kashmiri chili powder and ½ teaspoon of turmeric.
Add 3 chopped tomatoes, the pork with its marinade, and enough water to cover. Cover and simmer for about 1 hour, until the pork is very tender, adding a little water if needed.
Stir in the fried garlic and season with salt and a squeeze of lime juice.
