Step 1

Bring a large Dutch oven or other pot of water to a boil and salt it generously.

Step 2

Meanwhile, smash the garlic; roughly chop the walnuts. Combine the oil and garlic in a small saucepan and place it over medium heat. Cook, pressing down on the garlic with a wooden spoon to help break it into smaller pieces, until oil is sizzling, and garlic is very light golden, 1 to 2 minutes. Add the walnuts and stir to coat; season aggressively with pepper (this is the "pepe" part of the cacio e pepe). Cook, stirring and tossing frequently, until garlic and nuts are golden-brown, 3 minutes more. Remove from the heat and season with salt.

Step 3

Boil the pasta, stirring occasionally, until very al dente. In the meantime, grate the cheeses on the large holes of a box grater (you should have about 3/4 cup when combined); roughly chop the parsley. Set the cheeses and parsley aside separately.

Step 4

Scoop out 2 cups pasta cooking liquid, then drain pasta and return it to the pot over medium heat. Scrape in the walnut-garlic mixture and add about 1 cup pasta cooking liquid. Stirring continuously, gradually add about 1/3 cup cheese and cook, still stirring, until cheese melts and liquid thickens. Add another 1/2 cup pasta liquid and half the remaining cheese and simmer, stirring, until cheese is melted.

Step 5

Add the last bit of cheese and cook, adding big splashes of pasta water as needed until the sauce becomes glossy and emulsified and lightly coats the pasta. Turn off the heat. Add the parsley and stir to combine. Taste and adjust seasoning.

Step 6

Reprinted from " That Sounds So Good" by Carla Lalli Music. Copyright © 2021 by Carla Lalli Music. Photographs copyright © 2021 by Andrea Gentl and Martin Hyers. Published by Clarkson Potter, an imprint of Random House, a division of Penguin Random House LLC.