How to Make Alfredo Sauce (Authentic Italian Style)

Set up a glass bowl and grate the parmesan reggiano on a microplane. You want the cheese fluffy and powdery, not chunky. Fine grating means the cheese melts the instant it hits the hot pasta, which is what builds the emulsion.

Plan on roughly three-quarters of a pound to a pound of cheese for a pound of pasta. It looks like a lot. It is a lot. This dish is meant to be rich and you are not going to skimp here.

Bring a small pot of water to a boil. Use less water than you would normally for pasta. The whole point is to make the cooking liquid as starchy as possible so it can pull the sauce together later.

Salt the water lightly - much less than you'd usually salt pasta water. The parmesan is already very salty, and you don't want to push the finished dish over the edge. Drop in the dry fettuccine and stir occasionally.

While the pasta cooks, cube a stick of European-style butter into a glass mixing bowl. When the pasta is just past al dente - bite into a strand to check, no white center - turn off the heat.

Use tongs to lift the cooked pasta directly out of the pot and into the glass bowl. Don't drain. Don't strain. The starchy water clinging to the noodles is what's going to emulsify with the butter.

Start stirring immediately and don't stop. The heat from the pasta is what melts the butter, and the starchy water is what helps the butter coat every strand instead of pooling.

You'll see the butter cubes shrink and the bottom of the bowl turn glossy yellow. Keep moving. The motion is what builds the emulsion - if you walk away, the fat separates.

Add the grated parmesan a generous handful at a time. After each addition, stir until that batch is melted and incorporated before adding the next. The sauce thickens as the cheese goes in.

If the cheese starts to clump, you're moving too slow or the bowl has lost too much heat - speed up the stirring. The strands should look creamier with every pass.

If the sauce looks tight, dry, or clumpy, add a small splash of the reserved pasta water and keep stirring. The starch in the water is what gives Alfredo its signature silkiness.

Add water a tablespoon at a time. Stop the second the sauce turns glossy and the pasta strands ribbon cleanly off the tongs. It should look like there's heavy cream in there. There isn't.

Alfredo doesn't wait. The sauce stays creamy only while it's hot - once it cools, the butter starts to firm and the emulsion breaks. Have the plates ready before you finish the sauce.

Use tongs or a fork to twist the pasta into a nest on each plate. Add a small extra grating of parmesan on top if you want, but taste first - there's already a lot of cheese in there.