Put lamb, fat and Spanish onion through the finest blade of your mincer 3 times. Combine in a large mixing bowl with finely-chopped mint leaves, parsley, marjoram, salt, pepper and spices, to taste. Mix well. The kefta mixture should be very highly flavoured.
Form into little balls the size of a marble and poach gently in water for 10 minutes. Then sauté gently in butter until lightly browned.
Finally, simmer in kefta sauce for at least 10 minutes before serving. Serve in sauce or on a bed of rice with sauce apart.