Ingredients

  • Kosher salt
  • 1 pound spaghetti
  • 6 ounces bacon, chopped
  • Extra-virgin olive oil, if needed
  • 1 small onion, chopped (about 1 cup)
  • 2 large egg yolks
  • 1 bunch scallions, trimmed and chopped (about 1 cup)
  • 1 teaspoon freshly ground black pepper
  • 1 cup grated Grana Padano or Parmigiano-Reggiano

Method

  • Bring a large pot of salted water to boil.
  • Slip the spaghetti into the boiling pasta water, and stir.
  • Cook the bacon in a skillet over medium heat until the fat has mostly rendered, about 4 to 5 minutes.
  • (If your bacon is very lean, you can add a drizzle of olive oil to help start the rendering of the fat.)
  • Push the bacon to one side of the pan, and add the onion.
  • Let both cook separately until the onion is tender, about 5 minutes, then mix the two back together.
  • (If you like, you can drain off the excess bacon fat here and replace it with olive oil.)
  • Ladle 4 cups pasta water into the skillet with the bacon and onion, bring to a rapid boil, and quickly reduce the sauce.
  • Meanwhile, whisk the egg yolks with 1/4 cup hot pasta water in a small bowl.
  • When the sauce has reduced by about half and the spaghetti is al dente, scoop the pasta into the sauce with tongs or a spider.
  • Add the scallions, pepper, and salt to taste.
  • Toss the pasta until it is coated in the sauce and the scallions are wilted.
  • Remove the pan from the fire, and quickly mix in the egg yolks, stirring until creamy.
  • Toss the pasta with the grated cheese, and serve immediately.