Mix the butternut, olive oil, rosemary, cinnamon and salt in large bowl.
On a foil-lined baking sheet, spread the squash mixture evenly. Bake for 40-50 minutes, stirring occasionally, until tender with a fork.
In large pan over medium heat, add olive oil. When hot, add shallots, allowing them to cook until slightly golden. Add remaining pears, stock, and syrup. Bring to a boil.
In a food processor or blender, add squash mixture and pear-shallot broth mixture. Blend until smooth. Season to taste with more salt if needed.
Serve in soup bowls with a dollop of sour cream or creme friache; garnish with rosemary.