OPTION 1: Preheat oven to 400 degrees and line a baking sheet with foil. In a large bowl, combine cauliflower, 2 TBS melted butter, salt, and toss to combine. Place on a baking sheet and roast until the desired degree of tenderness (about 10 minutes for crisp-tender, 20 minutes for very tender). Remove from oven and place cauliflower in a gratin pan. (I liked this way better because I love the “caramelized” flavor cauliflower can have).
OPTION 2: Bring a large pot of chicken broth to a boil. Place cauliflower in the broth and boil for 5 minutes or until tender. Remove from heat and strain the cauliflower well. Place in a gratin pan. (Craig liked this way better because it was a soft and tender cauliflower that reminded him of a potato).
Meanwhile, in a medium saucepan over medium-low heat, melt 2 TBS butter. Whisk constantly until starting to lightly brown, about 2 minutes, and slowly add chicken broth and cream cheese. Once completely combined, add shredded cheese and stir to combine until smooth.
Pour cheese mixture over top of the cauliflower, sprinkle Parmesan cheese on top if using, and place in the oven on the middle rack. Turn broiler on low and cook until cheese sauce bubbles slightly. Remove from oven and serve immediately.