• Preheat oven to 375°.
• Combine the pumpkin and onion in a mixing bowl with the oil and curry powder. Mix together until well coated. Spread out on a sheet pan and roast until slightly browned and tender, about 25 minutes. Set aside.
• In a soup pot, melt 2 tablespoons butter over medium high heat until it stops sizzling, add mushrooms and cook until tender. Season to taste with kosher salt and fresh ground pepper. Remove from pan, set aside in a warm place.
• Add the rest of the butter to the soup pot and heat until it stops sizzling. Add flour and brown sugar and cook, stirring constantly for about 5 minutes. Add vegetable stock and whisk together until smooth. Add pumpkin and onion to soup pot and bring to a boil. Turn off heat and puree soup with a hand immersion blender or food processor to a smooth consistency. Return to the soup pot and bring to a low simmer. Add salt and pepper to taste. Stir in cream and keep warm until serving.

To serve

• Ladle soup into 8 bowls and spoon sliced mushrooms over each. Serve immediately.