Monday was a busy day, and I asked our 16yo (who is good at heating a can of baked beans 🙂) if he would make it. He did, and it came out FLAWLESSLY. I asked my son if it was really "that easy," and he firmly (and enthusiatically) said YES!. He said that the only issue was that as it cooled, the cheese would turn back to cheese (you don't make a sauce, per se). This is currently an issue lately because sometimes (often) it takes DH a bit longer than planned to get off the phone with work. DS said he just turned the burner back on low and that was enough warmth to keep the cheese saucy.
Here's what he did:
Brought 6 cups of water + 1 tsp salt to a boil.
Cooked the pasta (we used penne) for the amount of time on the package. HE DID NOT DRAIN THE REST OF THE WATER. He did keep stirring almost the entire time the pasta boiled so it wouldn't stick.
Then, he stirred in
4 oz of cream cheese, cut into cubes
1/4 cup of parmesan cheese
2 cups of shredded cheddar
The cheddar turned it a kind of crazy orange. I'd probably use some monterey jack if buying cheese, but I just used what we had on hand.