1. Preheat oven to 400° F
2. Cook the noodles in a large pot of salted water, until just barely tender, 5 to 6 minutes. Drain and set aside.
3. Meanwhile, place the cheeses in a large bowl, tossing to combine. Remove 1 cup of the shredded cheese blend and set aside to reserve for the topping.
4. In the same pot you boiled the noodles in, melt the butter over medium heat. Once the butter is melted, add the garlic, and cook until fragrant, 1 to 2 minutes. Sprinkle in the flour, nutritional yeast, garlic powder, mustard powder, smoked paprika and nutmeg, and whisk to combine.
5. Cook for 1 to 2 minutes, then slowly whisk in the milk until there are no clumps and the sauce is nice and thick – it should be able to coat the back of a spoon.
6. Working in batches, add the 4 cups of cheese to the pot, stirring to combine.
7. Once the cheese is added and mostly melted through, season with the salt and pepper. Taste and adjust seasonings, if necessary.
8. Slowly fold in the noodles, ensuring they’re thoroughly coated in the cheese sauce. Taste and adjust seasonings if necessary.
9. Transfer the mac and cheese to a prepared 9x13-inch baking dish and top with the reserved cup of cheese. Cover loosely with foil and bake until the cheesy topping is melted, 20 to 25 minutes.
10. Remove the foil and continue to bake until golden and bubbly, another 10 to 15 minutes. If you’d like you can broil it the last 2 to 3 minutes or so.
11. Garnish with parsley and enjoy!