The flavour of the soup is so much more intense if the pumpkin is roasted beforehand. I always try to use the variety Ironbark when available, as it has a very good strong colour and sweet flavour.
Preheat the oven to 160°C/gas 3. Cut the pumpkin into equal-sized segments and remove the seeds. Wrap in foil and roast in the oven until soft, about 45–60 m