1kg lamb, 200g mutton fat, 2-3 onions, 1 tsp salt, 1 tsp Zira (cumin), 2 tsp coriander  seeds, 1 tsp black or red pepper, 2 tbsp vinegar.
Cut the lamb flesh and the fat into pieces of 15-16g. Salt and pepper them, sprinkle coriander. Add finely chopped onion and vinegar. Mix all well. To marinate better, put all this in an enamel bowl, press on top with the load, cover with gauze and put the bowl in a cool place for several hours (4 to 24).
Then string on skewers for 6 pieces, the last piece - the fat. Roast over the coals, first on one side then the other to release the juice and golden brown. Swing occasionally with a fan, to increase heat and fry the meat evenly. If the fat runs down and makes a flame, sprinkle the coals with water.
When serving, garnish with rings of white onion, sliced cucumbers or tomatoes. You can separately supply fresh vegetables (tomato, cucumber, and radish) or a salad of them.