6 quarts cold water
4 tablespoons Kosher or sea salt
1/4 cup extra-virgin olive oil
4 ounces fatty pancetta, sliced a quarter-inch thick and rough-chopped
Freshly ground black pepper to taste
1/2 cup finely diced red onion
2 cloves fresh garlic, minced
2 whole large eggs, chilled
1/2 pound dried name-brand spaghetti
1/2 cup lightly-packed Parmigiano-Reggiano cheese
First, bring a heavy 8-quart stockpot of well-salted water to a rapid boil over high heat.
At the same time, in a heavy10-inch skillet heat the olive oil over medium heat.
Then drop in the pancetta and 1/2 teaspoon of the black pepper and cook, stirring occasionally, until the pancetta turns golden and begins to crisp (which should all of about 5 minutes).
Note: If the meat is browning too quickly, reduce the heat to medium low.
When the pancetta is done, add in the onion and continue to cook until it softens, becomes golden, and turns crisp (about another 5 minutes).
At this point, remove the skillet from the heat and carefully spoon off all but about 2 tablespoons of the fat.
Then add one tablespoon of water to the pan and scrape any brown bits from the bottom.
This is the deglazing process it shouldn't be omitted because it lends volumes of flavor to the finished dish.
Now it's time to beat the eggs in a small bowl until smooth but set them aside for a moment. This is also the time to cook the spaghetti in the boiling water all you need to do is follow package directions. If it's done properly, it will turn out just short of al dente.
When that's done, drain off the cooking water...but reserve 1 cup. Then transfer the pasta to the skillet, set it back over medium heat, and toss it with tongs to coat it with the pancetta fat. Continue cooking until it turns it actually becomes al dente (that should take about a minute or so).
Hint: If, in the process, you find that the pasta is drying out or it starts to stick to the bottom of the pan, add 1 or 2 teaspoons of the pasta water. You want the bottom of the pan to be 'just barely wet.' If it is too dry, the eggs will scramble as soon as you add them.
Finally, remove the skillet from the heat once again and pour the eggs over the pasta, tossing quickly and continuously, until the pan liquid thickens and reaches the consistency of a thin custard (this will take 30 seconds to a minute). Oh, by the way tossing the pasta constantly is important because it prevents the eggs from scrambling.
By this time the pan sauce should be smooth and creamy and it should easily cling to the spaghetti.
Should it become necessary to loosen the sauce a tad, simply add a little more pasta water.
All you need to do now is stir in the Parmesan cheese and season the finished dish to taste with salt and pepper (you may not need additional salt because the pancetta can sometimes be very salty).
That's Pasta Carbonara and it is best if served immediately when it comes off the fire.