Grind the ingredients 1-7 together to make a paste and set aside.
Heat the oil in a pan and fry the onions until golden. Add tomatoes and fry for 5 minutes. Add the spice paste and fry for another 5 minutes. Put the lamb pieces and pour the vinegar and mix well. Stir-fry for 10 more minutes. Add salt and some water. Cover and cook over medium heat until the meat is tender and the gravy becomes thick. Serve garnishing with chopped coriander leaves.