Cook the split peas in a small saucepan of boiling water for about 20 minutes. Meanwhile, soak the rice in a bowl of water.
Heat the oil in a large frying pan, then sauté the onion over medium heat for about 5 minutes. Add the turmeric, then seal the lamb in this mixture for 3–5 minutes. Stir in the tomato paste and cook for a few minutes, until its colour brightens slightly.