Butternut Squash Soup with Cider Cream

5 tablespoons butter
2 1/2 pounds butternut squash, peeled, seeded, cut into 1/2-inch pieces (about 6 cups)
1 large onion, chopped
1 chopped peeled carrot
1 chopped celery stalk
2 small Granny Smith apples, peeled, cored, chopped
1 1/2 teaspoons dried thyme
1/2 teaspoon crumbled dried sage leaves
5 cups chicken stock or canned low-salt chicken broth
1 1/2 cups apple cider
2/3 cup sour cream
1/2 cup whipping cream
Chopped fresh chives

Heat oven to 450 degrees.  Toss butternut squash with olive oil and salt.  Roast 40 minutes or until nicely browned.  Meanwhile, melt butter in heavy large saucepan over medium-high heat. Add onion, carrot and celery; sauté until slightly softened, about 15 minutes. Mix in apples, thyme and sage. Add stock and 1 cup cider and bring to boil. Reduce heat to medium-low. Cover and simmer until apples are tender, stirring occasionally, about 30 minutes. Cool slightly.  Add roasted butternut squash

Working in batches, purée soup in blender. Return soup to pan. Boil remaining 1/2 cup cider in heavy small saucepan until reduced to 1/4 cup, about 5 minutes. Cool. Place sour cream in small bowl. Whisk in reduced cider. (Soup and cider cream can be made 1 day ahead. Cover separately and refrigerate.)

Bring soup to simmer. Mix in whipping cream. Ladle soup into bowls. Drizzle with cider cream. Top with chives.