Preheat oven to 400*.
Bring 3-4" water to a rapid boil and steam cauliflower florets to fork tend. About 7-10 minutes. Drain cauliflower and set aside in a large clean bowl.
In medium saucepan over medium heat whisk together cream, cream cheese, garlic powder, onion powder, salt and dried parsley. Bring to a small simmer.
Add 2 cups of the shredded cheddar cheese to the simmering cream mixture. Gently stir until fully combined into a thick creamy cheese mixture. Remove from stove top.
Pour hot cheese mixture over the cauliflower. Gently fold cauliflower into the melted cheese to fully coat all pieces. Transfer cheese covered cauliflower to a 6x10" casserole dish and smooth top to spread to all corners.
Sprinkle remaining 1/2 cup cheddar cheese and 1/2 cup parmesan cheese over the top of the cauliflower.
Bake for 15 minutes at 400*.
Optional...turn oven to broil to slightly brown and crisp up the top of your Cauliflower Cheese Casserole. Broil for 1-2 minutes.
Remove from oven and enjoy