Preheat the oven to 400°F (200°C).
Place the squash and sweet potato cubes in a bowl.
Drizzle with olive oil, salt, and pepper.
Spread them on a baking sheet.
Roast for 25–30 minutes until soft.
Heat a pot with a little olive oil.
Add the chopped onion. Cook until soft.
Add the garlic. Cook for 1 minute.
Put the roasted squash and sweet potatoes into the pot.
Pour in the vegetable broth.
Let it simmer for 10 minutes.
Blend the soup until smooth and creamy.
Stir in coconut milk, cinnamon, and nutmeg.
Taste and add more salt or pepper if needed.
Serve hot with fresh herbs on top.