Peel the pumpkin and scrape out the seeds. Cut the flesh into bite-sized cubes.
Put the pumpkin cinnamon stick, cloves in a saucepan. Add the water and bring to the boil. Simmer, under cover and on low heat, for 20-25 minutes until tender.
Remove the spices, then blend the soup until smooth and creamy. Add the vinegar, butter, then season with salt and pepper & sugar ( maple syrup) to your taste. If the soup is too thick, add some more water and heat it up again.
Serve with a dollop of sour cream and chopped chives scattered on the top, if you like.