Add cauliflower and reduce heat to medium. Cook cauliflower until very tender, about 10 minutes; drain, shaking the colander to remove as much water as possible.
Blend drained cauliflower and cream in a blender until smooth; transfer to a pot over low heat.
Stir Parmesan cheese, butter, cream cheese, and sea salt through the blended cauliflower; cook and stir until hot, about 5 minutes.