Peel squash, then scoop out pulp and seeds.
Cut up squash and onions.
Heat oil in large soup pot. Add squash and onion and saute a few minutes.
Add broth to pot. Cover and simmer 20-30 minutes until vegetables are tender.
Use a ladle, scoop soup into blender and blend until smooth (or use an immersion blender, if you have one). You may need to divide the soup to do this.
Return pureed soup to pot. Add and adjust spices to taste.
If desired, add a scoop of creme fraiche or drizzle of cream just before serving.