Roast the coriander and cumin seeds in a small pan. Transfer to a coffee/spice grinder or mortar and pestle. Add the chillies, peppercorns and mustard seeds and grind for a moment or two. Transfer to a bowl. Add the vinegar, salt and sugar and stir well. Set aside.
In a deep flameproof casserole, heat the oil and fry the onions until really brown. Then add in the garlic, ginger and turmeric. Stir in the cream. Add the cardamom seeds, cinnamon stick and chopped tomatoes. Simmer gently while you brown the meat.
In another pan heat some extra oil and brown the meat well. Transfer the meat as it browns to the sauce. Stir in the vindaloo paste. Cover the casserole and cook for 50-60 minutes.
Taste for seasoning. Serve with and a bowl of cucumber raita – grated cucumber mixed with plain yoghurt, seasoned with salt, ground cumin and chopped mint. Also delicious served with the pork are cubed potatoes boiled in turmeric flavoured water, with cauliflower florets added in for the last 3-4 minutes. When cooked, drain well and toss in hot oil seasoned with cumin seeds, chopped scallions and chopped chilli. Delicious!
Shortcut: Use a good quality ready made vindaloo or curry paste.