Combine creamed corn and onion in a blender. Process until pureed and strain into a saucepan. Add pumpkin, broth, orange juice, cornstarch, coriander, salt, nutmeg, and black pepper. Mix well and bring to a boil, stirring occasionally, 5 to 10 minutes. Stir in heavy cream; heat until warmed through, but do not boil, about 5 minutes more.
