Step 1

Cook the spaghetti in a large pot of generously salted water.

Step 2

While the spaghetti cooks, whisk together the milk and egg in a small bowl.

Step 3

Once the pasta is cooked al dente, drain.

Step 4

Put the drained pasta back into the cooking pot. Turn the heat to low, add the milk/egg mixture and butter, and stir just until the milk thickens and coats the noodles, a minute or so.

Step 5

Remove from heat. Add the cheese and stir again. Taste and add salt and pepper to taste. If the pasta gets too sticky, thin it with a little more milk.

Step 6

Serve immediately with more Pecorino Romano at the table.