Soften chopped onion in butter in a large pan for 10 minutes over low heat.
Add 1kg of diced pumpkin and stir for 3 minutes over medium heat.
Add 800ml hot stock and 110g parmesan, then simmer for 10 minutes and season.
Blend the soup in batches using a food processor until completely smooth.
Pass the soup through a fine sieve into a clean pan and warm through.
Dry fry pumpkin seeds in a hot pan until toasted.
Add vegetable oil and fry seeds for 5 minutes until golden-brown.
Sauté 25g pumpkin cubes in 5ml olive oil until softened and set aside.
Fry diced ceps in 10ml olive oil for 3 minutes, then stir in chives.
Ladle soup into bowls and garnish with cooked pumpkin, parmesan cubes, ceps, seeds, and olive oil.