Heat oven to 350 degrees F. In roasting pan, mix squash and 2 tablespoons oil. Arrange squash, curved side up; place garlic in curved part of squash.
Roast in 350 degree F oven 1 hour or until tender. Turn halfway through cooking.
In large pot, heat remaining oil. Add onion; sauté 5 minutes, until softened. Add squash, garlic, apple, broth, cider, salt, black pepper and nutmeg. Bring to a boil over high heat. Cover; reduce heat to medium. Simmer 25 minutes, until apple and squash are very soft.
Working in batches, puree soup in food processor. Rewarm. Garnish with sour cream and cinnamon. Makes 8 servings.