It’s an incredibly simple and quick dish with only a few key ingredients. The result is pasta that’s impressively elegant and rich, and loaded with the flavors of sweet, young Parmigiano-Reggiano cheese and butter. The key is to use the starchy pasta-cooking water to form a smooth, creamy, emulsified sauce…minus the cream.
1 stick unsalted butter (115g), diced
4 ounces Parmigiano-Reggiano cheese (115g), grated on the fine holes of a box grater, plus more for serving (see note)
1 pound fresh fettuccine pasta
In a large heatproof bowl, combine butter and cheese. In a medium pot of salted boiling water, cook pasta until al dente. Using tongs, a strainer, or a spider, transfer pasta to bowl with cheese and butter.
Add 1/2 cup hot pasta-cooking water, then, using tongs, toss repeatedly until butter is melted and a creamy, emulsified sauce forms. If pasta seems too dry, add a splash or two of additional pasta water until desired consistency is reached. Season with salt, if necessary. Serve, sprinkling more cheese on top at the table.