In a large pot, heat the ghee or coconut oil over medium heat.
Add the chopped onion and sauté until it becomes translucent.
Stir in the minced garlic and grated ginger and cook for another 1-2 minutes until fragrant.
Add the diced pumpkin and sauté for 5-7 minutes, allowing it to develop some color.
Sprinkle the turmeric, cumin, coriander, and black pepper over the pumpkin. Stir well to coat the pumpkin in the spices.
Pour in the vegetable broth and bring the mixture to a boil. Reduce the heat, cover, and simmer for about 20-25 minutes, or until the pumpkin is soft and can be easily mashed with a fork.
Use an immersion blender to puree the soup until smooth. Alternatively, transfer the soup to a blender in batches and blend until smooth.
Return the blended soup to the pot and stir in the coconut milk. Cook for an additional 5 minutes, allowing the flavors to meld together.
Season the soup with salt to taste.
Serve hot, garnished with fresh cilantro leaves.