True fettuccine al burro (what Americans call Alfredo) is a study in emulsion: butter and finely grated Parmesan bound together by the starch in pasta water into a creamy sauce — with no actual cream. The whole trick is temperature and tossing.

Ingredients

  • 400 g (14 oz) fettuccine
  • 120 g (1 stick) unsalted butter
  • 120 g (1½ cups) Parmigiano-Reggiano, finely grated
  • Salt for the pasta water
  • Freshly ground black pepper

Method

  1. Cook the fettuccine in well-salted water until al dente. Reserve at least 1½ cups of pasta water before draining.
  2. In a wide pan over low heat, melt the butter with a ladleful of pasta water, swirling to make a cloudy emulsion.
  3. Add the drained pasta and toss to coat. Turn off the heat.
  4. Add the Parmesan in handfuls, tossing constantly and adding splashes of pasta water, until a glossy sauce forms and clings to the noodles. Keeping it off direct heat stops the cheese clumping.
  5. Finish with lots of black pepper and serve immediately — Alfredo waits for no one.

🧀 Finely grate the Parmesan

Use a fine grater or microplane and real Parmigiano-Reggiano. Coarse or pre-shredded cheese won't melt smoothly and you'll get clumps instead of silk.