Wash the sweet pumpkin thoroughly, remove the seeds, and cut into bite-sized pieces.
Thinly slice the onion and dice the potato.
Heat olive oil in a pot, then sauté the onion and potato.
Add the sweet pumpkin and stir-fry together, then pour in water and boil until the ingredients are cooked.
Once the ingredients are soft, turn off the heat and blend everything smoothly with a hand blender.
Return to low heat, add milk or fresh cream, and simmer while stirring well.
Season with salt and pepper, pour into a bowl, and serve.