Mansaf is a popular Jordanian dish typically served at weddings and large gatherings. Made of lamb cooked in a spiced yogurt sauce and served over buttery rice and thin flatbread, this meal is commonly eaten with your hands, but is tasty any way you consume it.
Heat 1/4 cup ghee in a large heavy-bottomed pot or Dutch oven over medium-high heat. Add the lamb, 1 tablespoon salt and a few grinds of black pepper to the pot and cook, stirring once or twice, until well browned on all sides, 6 to 7 minutes.
Add the diced onions and stir. Add enough water to cover the lamb and onions and bring to a boil. Reduce the heat to a simmer, cover and cook until the lamb is just tender, about 45 minutes.
When the lamb is close to done, heat the yogurt, lemon juice, egg white and a pinch of salt and black pepper in a medium saucepan over medium heat, whisking until combined. Bring to a boil, then add the cumin, cardamom, coriander, cinnamon and allspice and stir to combine. Reduce the heat to low and simmer, whisking frequently, until thickened slightly, 10 to 15 minutes.
Meanwhile, bring the rice, 3 cups water and a pinch of salt to a boil in a medium saucepan over medium-high heat. Cover and simmer for 15 minutes. Turn the heat off and let sit 10 minutes.
Heat the remaining 2 tablespoons ghee in a small skillet. Add the almonds and cook, shaking the pan occasionally, until the almonds are toasted and golden, 4 to 5 minutes. Top with a pinch of salt and remove from the heat.
Pour the yogurt mixture into the pot with the lamb and stir to combine. Simmer, covered, until the lamb is fully tender and can easily be shredded with a fork, 20 to 25 minutes.
Fluff the rice with a fork. Stir in the butter and turmeric. Taste and add salt if necessary. Set aside.
Spoon the rice onto a large platter. Use a slotted spoon to transfer the lamb on top of the rice. Ladle the broth over the top until the rice looks well saturated (you will not use all the broth). Sprinkle with the almonds and parsley. Pour the remaining broth into a serving bowl and serve alongside the platter. Sprinkle the sliced onions with the sumac and serve on the side to use for scooping.