1. In a large heavy saucepan over very low heat, melt half the butter. Add the pumpkin pieces and onion, toss to coat with the butter, and gently cook until the onions are translucent, tossing frequently.
2. Add the broth or water and season with salt and pepper to taste. Increase the heat and bring to a boil. Reduce the heat and simmer for 30 minutes, or until the pumpkin is soft.
3. Using a slotted spoon, remove the pumpkin and onion from the pot to a food processor or blender, in batches, and process until smooth. Put the purée in another pot and stir in enough of the cooking liquid until the desired consistency is reached. Taste and adjust the seasoning.
4. Add the remaining butter and reheat over low heat, stirring frequently. Sprinkle servings with some crispy croutons, if desired.
From: Boisset, C. (1997). Pumpkins & squashes, Gardering, Crafts & Recipes, Reader’s Digest: New York/Montreal.