Tonnarelli are Rome’s answer to spaghetti, but with more bite and a rustic edge. Traditionally, they’re made from flour and eggs, square in cross-section, and have a pleasantly firm, almost chewy texture that holds up beautifully to bold sauces. They’re rolled and cut on a chitarra, a wooden frame strung with taut metal wires that slices the sheet of dough into perfectly uniform strands. This technique connects tonnarelli to spaghetti alla chitarra, an Abruzzese specialty—which makes total sense given the long history of migration from Abruzzo to Rome. Even today, you’ll meet plenty of Roman cooks and bakers with roots east of the Apennines.

While you can make tonnarelli by hand, hardly anyone does in Rome. Most people buy them from pasta shops or the supermarket, where they’re always extruded. Even small pastifici skip the traditional rolling and cutting method in favor of machines that deliver consistent results with less labor.

There’s no single dough formula for tonnarelli. Some versions are made with whole eggs, others with egg whites only; others use water. Whole eggs bring both protein and fat to the dough—the whites help build structure, while the yolks lend richness and a supple texture. Then there’s the flour. Some doughs use all 00, while others mix in semolina for extra bite and backbone. The proportions of moisture and flour—and whether the pasta is rolled or extruded—ultimately shape the noodle’s personality, from toothsome and smooth to compact and rough. Whatever the dough, tonnarelli are the ideal vehicle for rich, clingy sauces like cacio e pepe.