1In large saucepan, combine squash, broth, water and pepper. Cook over medium heat until squash is tender, about 20 minutes.
2Blend until smooth (do this by very carefully transferring batches to a blender, using an submersion blender, or, what I do is use a potato masher - I don't mind the slightly lumpy texture at all, and actually prefer it).
3Bring mixture just to boiling; reduce heat and simmer uncovered for about 5 minutes. Add butter; stir until melted.