Begin your Christmas feast with this luxuriously rich soup served in pumpkin shells. It makes an impressive appetizer, especially when garnished with Spicy Pumpkin Seeds, which you won't be able to quit eating.
Remove stem end of pumpkins by slicing about 1 1/2" off top. Scoop out seeds; reserve seeds of 2 pumpkins. Place pumpkins and tops, cut side down, on greased large baking sheets. Bake at 375° for 35 to 45 minutes or just until tender. Cool 30 minutes. Gently scoop out most of pulp from all 8 pumpkins, leaving enough pulp in 6 shells so they are intact for serving. Set aside 2 1/4 cups pulp.
Place onion and apple in a large saucepan; add 1 1/4 cups chicken broth. Bring to a boil; cover, reduce heat, and simmer 30 to 40 minutes or until very tender. Process pumpkin pulp and onion mixture in a food processor until smooth. Return mixture to saucepan; add remaining 1 cup chicken broth, half-and-half, curry powder, and salt. Cook over medium heat just until soup comes to a simmer. (Do not boil.)
Place pumpkin shells on individual serving plates. Spoon soup into each shell. Dollop with sour cream, and sprinkle with Spicy Pumpkin Seeds. Add pumpkin tops, if desired.