01 - Preheat the oven to 400°F. Toss cubed squash with 1 tablespoon of olive oil, salt, and pepper, then spread evenly on a baking sheet. Roast for 25 to 30 minutes until tender and lightly caramelized.
02 - Heat the remaining tablespoon of olive oil in a large pot over medium heat. Add chopped onion, carrot, and celery, cooking for 6 to 8 minutes until softened. Stir in minced garlic and cook for an additional minute.
03 - Add the roasted squash to the pot with cumin, nutmeg, and cinnamon. Pour in the vegetable broth, bring to a boil, then reduce the heat and simmer gently for 10 minutes.
04 - Remove the pot from heat and purée the soup until smooth using an immersion blender or standard blender in batches.
05 - Stir in the heavy cream or coconut milk, adjusting salt and pepper to taste. Reheat gently if necessary.
06 - Ladle the soup into bowls and garnish with toasted pumpkin seeds, chopped parsley, and a drizzle of cream if desired.