- 2 tablespoons olive oil
- 1 large red onion, finely chopped (2 cups)
- 2 garlic cloves, finely chopped
- 6 ounces thinly sliced fine-quality prosciutto, such as Prosciutto di Parma, finely chopped and separated into pieces (1 1/2 cups)
- 2 (28-ounce) cans Italian plum tomatoes in juice, drained, reserving juice, and finely chopped
- 1 teaspoon sugar
- 1 pound penne rigate
- Accompaniment: Parmigiano-Reggiano (shavings or finely grated )
- Heat oil in a wide heavy medium pot over medium-high heat until it shimmers, then sauté onion until golden, about 10 minutes. Add garlic and sauté until golden, about 1 minute. Add prosciutto and sauté until golden, about 4 minutes. Add tomatoes with reserved juice, sugar, and 1/4 teaspoon each of salt and pepper and simmer, uncovered, stirring occasionally, until thickened, 45 minutes to 1 hour. Cool, uncovered, then chill, covered, at least 8 hours (to allow flavors to develop).
- Cook penne in a pasta pot of boiling salted water (3 tablespoons salt for 6 quarts water) until al dente. Drain well.
- While pasta cooks, reheat sauce over medium heat.
- Toss pasta with some of sauce in a serving bowl and serve remaining sauce on the side.