It was a memorable lunch: The porky guanciale was at the forefront, followed by the heat of the pepper and the tang of the cheese; it all formed a rich yet delicately creamy sauce to coat the rigatoni.
But when I made the dish (using pancetta since guanciale can be hard to find), it became clear that the technique was more art than science: As the al chiodo pasta cooks through, it absorbs some of the pasta water and releases starch to help emulsify the water and fat into a creamy sauce. How much pasta water to add depends on knowing how much more cooking the pasta needs and how much water it will absorb. And if there isn’t enough pasta water to maintain the emulsion, the sauce will be broken and greasy. I wanted to remove the guesswork for those times when I can’t give dinner my undivided attention.
That would mean using the more straightforward approach of adding al dente pasta to a finished sauce. But rather than use the standard 4 quarts of water to boil the pasta, I scaled the water to 2 quarts (unsalted since the pancetta and Pecorino contributed plenty of salt). This way, the water would have double the starch, which would help ensure emulsification.