Tomato, Pancetta and Onion Sauce for Pasta
                            (from America's Test Kitchen)

This is a sauce for pasta all'Amatriciana. This dish is traditionally made with bucatini, also called perciatelli, which appear to be thick, round strands but are actually thin, extralong tubes. Linguine works fine, too.

When buying pancetta, ask the butcher to slice it ¼". If using bacon, buy slab bacon and cut it into ¼"-thick slices yourself. If the pancetta that you’re using is very lean, it’s unlikely that you will need to drain off any fat before adding the onion. Use 1½ small (14½ oz) cans of diced tomatoes, or dice a single large (28 oz) can of whole tomatoes packed in juice.

Yield

Serves 4.

Ingredients

  2 tbsp extra-virgin olive oil
  6 ounces pancetta (¼"-thick sliced) or bacon, cut into strips about 1" long and ¼" wide
  1 medium onion, chopped fine
  ½ tsp red pepper flakes or to taste
  2½ cups diced tomatoes with juice
  1 pound bucatini, perciatelli, or linguine
  1/3 cup grated Pecorino Romano cheese (about 1½ ounces)

Preparation

1. Bring 4 quarts water to rolling boil in large stockpot or Dutch oven.

2. Meanwhile, heat oil in large skillet over medium heat until shimmering, but not smoking. Add pancetta or bacon and cook, stirring occasionally, until lightly browned and crisp, about 8 minutes. Transfer pancetta or bacon with slotted spoon to paper towel–lined plate; set aside. If necessary, drain all but 2 tbsp fat from skillet. Add onion to skillet; sauté over medium heat until softened, about 5 minutes. Add red pepper flakes and cook to release flavor, about 30 seconds. Stir in tomatoes and salt to taste; simmer until slightly thickened, about 10 minutes.

3. While sauce is simmering, add 1½ tsp salt and pasta to boiling water. Cook until pasta is al dente; drain and return pasta to empty pot.

4. Add pancetta to tomato sauce and adjust seasoning with salt. Add sauce to pot with pasta and toss over low heat to combine, about 30 seconds. Add cheese and toss again; serve.