Line a 4- to 6-quart slow cooker pot with parchment paper. Grease the parchment paper with butter.

In a large bowl, add the cream cheese, cheddar cheese, and heavy cream. Stir to combine.

Add the cauliflower florets to the cheese mixture and stir to coat the cauliflower completely with the cheese mixture. Add the sea salt and black pepper and stir.

Transfer the cauliflower mixture to the prepared slow cooker pot. Cover and cook on LOW heat for 4 hours.