Heat the oil or butter in a large pot over medium heat.

Add the sliced onions and sauté until translucent.

Stir in the minced ginger and garlic, cooking until fragrant.

Add the chicken pieces and cook until browned on all sides.

Incorporate cumin, cardamom, cinnamon, cloves, bay leaves, nutmeg, black pepper, and salt; stir to coat the chicken with the spices.

Pour in the tomato purée and diced tomatoes, cooking for a few minutes until combined.

Add the diced carrots and chicken stock cubes; stir well.

Pour in 4 cups of water and bring to a boil.

Add the rinsed basmati rice, and if using, the raisins; stir gently.

Cover and reduce the heat, simmering for 45 minutes, or until the rice and chicken are cooked through.

Serve warm with additional garnishes if desired.