Preheat your oven to 375F bake.
Grease a 13x9 casserole.
Empty the frozen cauliflower into a medium pot and cover with water.
Bring the cauliflower to a boil and cook for 8-10 minutes until tender.
Drain the cauliflower and return it to the pot.
Grab your potato masher (or food processor) and mash (or process) the cauliflower to a desired consistency.
Spread the mashed cauliflower into the bottom of the casserole dish.
Layer the chopped ham over the cauliflower and set aside.
In a medium sauce pan, mix the shredded cheese, sour cream, heavy whipping cream, and seasonings together over medium heat until the cheese is slightly melted.
Once melted, evenly pour the mixture over the layers of ham and cauliflower.
Top the casserole with the cubed cheese and put in the oven to bake for 40-45 minutes (or until the cheese on top browns).