Rub 1 tablespoon olive oil over the flesh of the pumpkin and place the slices on the baking sheet, with cut side down. Roast for 40 minutes or until flesh is tender and can easily be pierced with a fork. Set it aside to cool for a few minutes.
In a large pot, heat the remaining 1 tablespoon oil on medium heat. Then sauté onions for 3-4 minutes. Add garlic and sauté for another minute.
Scoop out pumpkin flesh and add to the pot. Then add broth and spices. Give it a stir. Cover with a lid, and let it simmer for 8-10 minutes.
Then uncover, and blend using an immersion blender. (You can also let the soup cool a bit, then transfer to a standalone blender to blend to a smooth puree. Be careful while blending to avoid hot splatters)
Add coconut milk, and stir well. Simmer for another 5 minutes.
Garnish with your choice of pumpkin seeds, coconut milk, and freshly crushed black pepper.