Rinse rice with water several times. The last water after rinsing should be completely clear. Wash lamb and cut into cubes. Peel 3 onions and carrots. Slice onion into thin semi-circles, and the carrots - in 1 cm long strips. Peel garlic but do not divide into cloves. Warm up a large cooking pot (or another pan with a thick bottom and walls), pour in the oil and heat it until a light haze. Add the remaining onion and fry it until black. Take onion out of the pot. Prepare zirvak (the basis of pilaf). Fry onion until dark brown for 7 minutes, stirring. Add meat and fry to crust. Put carrots and fry for 3 minutes without stirring. Then mix everything and cook for 10 minutes, stirring gently. Rub cumin and coriander with fingers or a pounder and add to zirvak along with barberry and salt. Reduce the heat to medium and cook for 7-10 minutes until the carrot is soft. Pour boiling water (2 cm high) into the pot. Put hot pepper. Slack the fire and simmer zirvak for 1 hour. Rinse rice once again and drain water. Put the rice on zirvak in an even layer, increase the fire to the maximum and pour hot- boiling water in the pot through a skimmer, so that it covers the rice with a layer of 3 cm. As soon as the water is absorbed, press the garlic bulbs into the rice, slack the fire to the medium and cook until rice is done. Slightly hit the rice with a skimmer. If the sound from the impact is dull, make a few punctures in rice to the very bottom using a stick. Level the surface out, cover the pot of pilaf first with a plate and then with a lid. Slack the fire to the minimum and leave for 30 minutes.