In a medium saucepan, sweat the onion until soft. Stir in the curry paste and cook 4-5 minutes over low heat, stirring with a wooden spoon. Put in the pumpkin, stock and salt. Bring to the boil, turn down heat and simmer until pumpkin is tender.
Remove from heat and cool a little before pureeing in a blender until smooth. Return to the saucepan, season with salt and add the coconut cream. Reheat, but don't boil.