Heat the vegetable oil in a large, heavy-bottomed Dutch oven or pot over medium-high heat. Add the lamb cubes and sear until browned on all sides, about 8-10 minutes.

Add the sliced onions to the pot and sauté until they are deeply golden brown and softened, about 7-8 minutes.

Stir in the carrot matchsticks, whole cumin seeds, salt, and black pepper. Cook for another 5 minutes until the carrots begin to soften and the spices are intensely fragrant.

Pour in the hot broth and nestle the whole head of garlic into the center of the meat and vegetable mixture. Bring to a boil, then reduce heat to low, cover, and simmer for 40 minutes until the lamb is perfectly tender.

Remove the lid and gently spread the rinsed rice in an even layer over the lamb and carrots. Do not stir the rice into the meat; it must remain layered on top.

Increase the heat to medium-high and let the liquid boil up through the rice. Once the liquid drops below the surface of the rice (about 8-10 minutes), reduce the heat to the lowest possible setting.

Poke 5-6 holes through the rice to the bottom of the pot using the handle of a wooden spoon to allow steam to escape. Cover the pot with a tight-fitting lid and steam for 20 minutes until the rice is tender and fluffy.

Remove the pot from the heat and let it rest, covered, for 10 minutes. Remove the garlic head, gently mix the fluffy rice with the tender meat and carrots, and serve warm on a large communal platter with a fresh tomato and onion salad.