The subtle sweetness of apple and the exotic flavor of curry powder elevate this creamy soup. Roasting the fruit and vegetables gives them a caramelized taste and enriches the final result.
In a small bowl, stir together the oil and vinegar. Brush the cut sides of the squash, the apple halves, and the onions with the oil mixture. Place the squash and apple halves, cut sides down, and the onions on the prepared baking sheet.
Transfer the squash flesh and onion and apple pieces to a large saucepan and add the broth, curry powder, cumin, and cayenne pepper, if using. Bring to a boil over medium-high heat and then reduce the heat to medium. Simmer until very tender, about 20 minutes. Remove from the heat and let cool. In a blender, purée the soup in batches until smooth. Return the soup to the pan, stir in the half-and-half, season to taste with salt and black pepper, and heat through over medium heat. (The soup can be prepared up to 2 days in advance and stored, tightly covered, in the refrigerator. Heat through before serving.)
Ladle the soup into warmed bowls and garnish with the walnut pieces and red pepper flakes, if using.
© 2011 All rights reserved. Published by Weldon Owen.