Preheat oven to 375 degrees.
Place cauliflower florets and whole garlic cloves in a steamer basket. Put about 1 inch of water in a pot, placing the steamer basket on top and cover with a lid. Bring water to a boil and then reduce heat, and steam the cauliflower until completely fork tender, about 25 minutes.
Transfer the cooked cauliflower and garlic cloves into a food processor. Pulse a few times to break up the cauliflower. Add the cream cheese, butter, parmesan, egg yolk and salt and pepper. Pulse the cauliflower until just smooth and then stop. Do not overblend but there should be no lumps. Taste again for more salt as cauliflower can be bland and add more if needed.
Butter a small shallow baking dish. Pour the cauliflower into the dish and smooth the top. Sprinkle more parmesan on top and place in the oven. Bake for about 20-25 minutes until starts to brown a bit on the edges. Remove from oven and let cool briefly.
Enjoy!