Start by chopping the core off the cauliflower and chop into similar sizes. Add to a pot of water and set to boil for 15 minutes.
Remove the cooked cauliflower from the pot and drain the water. To that pot add the butter and cook over medium heat to melt. Once melted whisk the flour 1 Tablespoon at a time and stir to combine. Now add the milk and continue to whisk until it starts thickening.
Now add salt, pepper, garlic powder, nutmeg then Parmesan.
Once you've added the spices and Parmesan whisk to combine then add 1/2 cup of the cheddar cheese and stir until melted and combined completely.
Add the cauliflower back into the pot and stir the sauce and cauliflower so that it covers every piece.
Put the cauliflower into a greased oven proof bowl then sprinkle with the reminding 1/4 cup cheddar cheese.
Put into a 350 degree preheated oven for 15 minutes. Enjoy!