1. In a large pot, heat oil over medium-high heat
2. Add the onions and saute until translucent
3. Add the garlic and nutmeg and cook, stirring, until fragrant
4. Add squash, parsnips, and chestnuts. Add enough stock to cover the vegetables
5. Reduce the heat and simmer soup until vegetables are tender, about 30 minutes.
6. Taste and season with salt and pepper. Remove the pot from the stove.
7. With an immersion blender, puree the soup until smooth. Taste again and adjust salt and pepper as needed
8. Serve hot.