Heat the oven to 350 degrees

Shred 2/3 of the cheddar and cut the rest of the cheddar into cubes. Set aside 1 cup of shredded cheddar for the top of the mac and cheese

Shred the mozzarella cheese and reserve 1 cup for the top

Add salt to a pot of water and bring it to boil.

Boil the elbow macaroni for 5 minutes then drain it

Warm milk in the microwave or stovetop for a minute or two but do not let it boil

Melt the butter in a cast iron enamel Dutch oven then mix in the flour. Cook for 2 minutes stirring with a whisk constantly. Don't let it brown

Whisk in the milk

Pour the milk into the butter/flour mixture and stir. Add shredded cheddar and mozzarella

Stir in shredded cheddar simmer and stir until you have a smooth sauce.

TURN OFF THE HEAT

Stir in the cooked macaroni, the cubes of cheddar cheese, the shredded mozzarella and grated Parmesan if you are using it

Stir in the dry mustard, white pepper, granulated garlic and onion powder

Smooth the top and sprinkle the reserved shredded cheddar and mozzarella on top of the mac and cheese