Cut the remaining cauliflower into florets. 2 inch sized pieces. This should be about 6 cups worth.
Combine florets, water and milk in a saucepan large enough to hold 8-10 cups.
Season with salt and pepper and cayenne pepper.
Bring to a boil and cook the mixture until the florets are fork tender, about 10-15 minutes.
Strain, reserving 2 cups of the cooking liquid.
Spread the drained florets onto a large rimmed baking sheet.
Bake ten minutes until slightly dry.
Transfer florets to a blender or food processor in batches and puree.
Add about a half of cup of the reserved milk mixture to the blender and blend until smooth.
Continue until all of the soft florets are blended to a smooth texture.
Return puree to same saucepan.
Taste for seasoning. Set aside and keep warm.