Preheat oven to 425 degrees. Spray a 9×9 inch baking pan (round or square) with cooking spray. Set aside.
Place a couple inches of water in a large pot. Once the water is boiling, place the cauliflower florets into the pot and cover. Steam for 10-12 minutes, until tender. Drain and return cauliflower to the pot. Or to steam cauliflower in a microwave: Place cauliflower in microwave safe bowl and microwave for 8 minutes. (Do NOT cover or add water).
Frozen Cauliflower: If you are using frozen cauliflower, you may steam it in for about 5-6 minutes in the microwave until thawed and tender).
Add the seasonings and cheeses to the cauliflower, and stir to combine.
For a smooth texture: Using an immersion blender or food processor, combine the ingredients until smooth like mashed potatoes.
For a chunkier texture: Mash everything together with a potato masher (like you would mashed potatoes) if you want a thicker chunkier texture.
Scoop the cauliflower into prepared baking dish, and smooth with a spatula (I piped mine on using a large ziplock bag with the corner snipped off to make it look really pretty!) Sprinkle 2 tbs parmesan cheese over the top. Bake in preheated oven for 30 minutes, or until the topping is lightly golden brown. (Note you may also broil it for the last minute to get the top golden). Enjoy!