Wash the sweet pumpkin thoroughly, remove the skin and seeds, and cut into small pieces.
Finely chop the onion and garlic.
Melt butter in a pot and sauté the onion and garlic.
Add the sweet pumpkin and stir-fry for a while longer.
Pour in water or vegetable stock and boil until the pumpkin is tender.
Blend smoothly using a hand blender or mixer.
Add heavy cream and cream cheese, stir well, and bring to a gentle boil.
Season with salt and pepper to taste, then serve.