Preheat oven to 400. Combine butter, brown sugar and cinnamon. Spread butter mixture evenly over one side of each bread slice. Place bread, buttered side up, on a baking sheet. Bake 8-10 minutes or until bread is crisp and topping is bubbly. Cut each slice of bread into 8 small triangles or squares.
Sauté onion in butter in a medium saucepan until tender. Add 1 can chicken broth. Stir well. Bring to a boil, cover, reduce heat and simmer 15 minutes.
Transfer mixture to a blender or food processor. Blend until smooth. Return mixture to saucepan. Add remaining can of broth, pumpkin, salt, cinnamon, ground ginger and pepper. Stir well. Bring to a boil, cover, reduce heat and simmer 10 minutes, stirring occasionally.
Stir in whipping cream and heat through. Do not boil. Ladle into individual soup bowls. Top each serving with cinnamon croutons.