This... this was a low-key life changer.
I made the recipe as it was originally done and it was pretty much the simplest, quickest thing I have ever made.
You need noodles (I used a simple pack of the "fresh" noodles from the supermarket, it took literally 2 minutes to cook), a block of decent Parmesan cheese that you will shred about a cup of (gotta go with a block that you shred yourself, the pre-shredded doesn't work), and four tablespoons of butter. That's it.
You boil the noodles per the package (it was 2 minutes for the ones I used), then pull them from the water and put them wet in a large bowl with the butter. Add a small amount of the water you boiled the noodles in (like 1/3rd cup or so) and then slowly add in the cheese, mixing it as you go. That's it. You can add more pasta water if you want it saucier, but mix it until the cheese and butter melts into a sauce and you are good to go.
With the fresh noodles, it maybe takes 5 or 6 minutes and was a very tasty and filling meal. Totally worth it.
Why not?
I think there is something that is generally added to prevent it from sticking together if I remember correctly. You could certainly try it, but grating a cup of parm is not too difficult and it tasty.
Interesting. I buy the "good" pre-shredded parm from the fancy cheese section and it melts pretty well in my depression mac and cheese. I wonder if I just got lucky with the brand they sell where I shop.
Anti-clumping agents are generally put in pre-shredded cheeses, but you can get bags of shredded "melting cheeses" that don't have them though. In my experience that's only a supermercado kinda thing. That said your "good" pre-shredded could also be in that category.