**Thicken the sauce while it’s cooking; don’t wait for it to cool.** For a cream-based Alfredo, the best first fix is to evaporate some water before adding the cheese.

Try this approach:

1. **Use heavy cream.** Milk or half-and-half will give you a thinner sauce with the same cooking time.
2. **Simmer uncovered, stirring frequently, until the cream coats the back of a spoon.** Judge by consistency rather than the recipe’s timer. As a useful benchmark, reduce 1½ cups of cream to about 1 cup.
3. **Turn off the heat and gradually stir in finely grated Parmesan.** Freshly grated cheese helps you get a smooth sauce. These steps are also used in [Jessica Gavin’s Alfredo recipe](https://www.jessicagavin.com/alfredo-sauce/).
4. **Toss immediately with hot, well-drained fettuccine.** If it becomes too thick, add reserved pasta water a tablespoon at a time. Serve promptly, preferably in warm bowls.

Reduction concentrates the flavor you already have; adding lots more cheese can make the sauce overly salty. Aim for a sauce that coats the noodles while hot—it will firm up a little more as you eat.

I couldn’t retrieve the linked recipe, so I can’t check its particular proportions.