I tasted this wonderful pasta dish at the height of summer when the sauce was made with fresh plum tomatoes.  Most of us only have access to tomatoes like these in a farmers market during the late summer, so I’m giving you the recipe using canned tomatoes.  You probably already have a favorite brand but if not, look for real San Marzano tomatoes imported from Italy or Redpack crushed tomatoes which are 90% as good.

Makes 4 to 6 first-course servings

2 tablespoons olive oil

2 tablespoons unsalted butter

1 small onion, peeled, root end trimmed but left intact, and halved

1 28-ounce can imported plum tomatoes, crushed, or domestic crushed tomatoes

3 large sprigs basil, rinsed, 2 folded together into a small bundle and tied with twine, the other sprig shredded for serving

1/2 teaspoon fine sea salt

1 pound penne pasta

Grated Parmigiano Reggiano for serving

  1. Add the oil and butter to a medium saucepan and set over low heat.  Add the onion halves, cut side down, and let the onion cook slowly and color, about 10 minutes.  Turn the onion and cook briefly on the other side.
  2. Stir in the tomatoes and salt and bring the sauce to an active simmer.  Regulate the heat so that the sauce simmers slowly.  Stir in the basil.
  3. Cook the sauce until the oil accumulates again on the surface, about 30 minutes.  Remove the onion and basil and discard the basil – you can save the cooked onion for another use.
  4. Bring a large pan of water to a boil and salt it.  Cook the pasta al dente.  A few minutes before the pasta is ready, reheat the sauce.  Dip out a cup of the pasta cooking water, then drain the pasta.  Stir the pasta into the sauce and turn off the heat.  Add a little of the pasta cooking water if the pasta seems dry.  Sprinkle with the shredded basil and stir in. 
  5. Serve immediately in soup plates and pass the grated cheese.