In a large pot, combine the meat, quartered onion, garlic cloves, cinnamon stick, cardamom pods, whole cloves, bay leaf, and water.
Bring to a boil over medium-high heat, skimming off any foam that rises to the surface.
Reduce the heat to low, cover, and simmer for about 1-1.5 hours, or until the meat is tender.
Remove the meat from the pot and set aside. Strain the broth and reserve it for cooking the rice.
In a large pot, heat the vegetable oil or ghee over medium heat.
Add the finely chopped onions and sauté until golden brown, about 5-7 minutes.
Stir in the minced garlic and cook for another minute.
Add the chopped tomatoes and cook for about 5 minutes, or until the tomatoes are soft.
Stir in the ground turmeric, ground coriander, ground cumin, ground cinnamon, ground black pepper, ground cloves, ground cardamom, and ground nutmeg. Cook for 1-2 minutes until fragrant.
Add the soaked and drained basmati rice to the pot and stir to coat the rice with the spices.
Pour in the reserved broth, adding enough to cover the rice by about 1 inch (2.5 cm). You may need about 4 cups (960 ml) of broth.
Add salt to taste and bring the mixture to a boil.
Reduce the heat to low, cover, and simmer for about 20 minutes, or until the rice is cooked and the liquid is absorbed.
While the rice is cooking, in a separate small skillet, lightly toast the raisins and slivered almonds until golden brown.
Once the rice is cooked, gently fold in the cooked meat.
Transfer the machboos to a serving platter.
Garnish with toasted raisins and slivered almonds.
Sprinkle with fresh cilantro or parsley if desired.
Enjoy your meal!