Start by chopping your cauliflower into chunks. Try to make them as uniform as possible.
Place the cauliflower in a pot of salted, boiling water. Boil for about 4-5 minutes or until fork tender. Drain the water and allow the cauliflower to cool slightly.
Dump the cauliflower out onto a clean kitchen towel or some cheesecloth and wring out the extra liquid. Don't be afraid of removing too much liquid. You can always add a little extra water or chicken broth if it seems to dry later on.
Return the cauliflower to the pot and add in the butter, cream cheese, heavy cream, salt and pepper. Using a potato masher if you prefer a lumpier texture, or a hand mixer for a smoother texture. mix everything until it's all well integrated. (If your cauliflower is too cool to melt the butter and cream cheese, place it over low heat, stirring constantly until everything has melted.) Taste your mashed cauliflower and add more salt or pepper if needed.