In a pot, heat oil over medium heat. Add onion and garlic. Cook until onion is softened, about 5 minutes. Add squash, vegetable broth, sea salt and star anise (if using). Simmer uncovered for 20 minutes, until butternut squash is very tender.

If using star anise, take it out of the soup and discard before blending. Using an immersion blender or regular blender, blend soup until smooth. Add sea salt, to taste. Serve topped with cilantro or parsley (optional).