Stir in the onion; cook for 5 to 8 minutes, until the onion softens and becomes translucent. Add the pasta; cook for 2 minutes less than the package directions indicate (to al dente consistency). Before draining the pasta, reserve 1/2 cup of the pasta cooking water. Step 3Pour the warm sauce over the pasta and toss to coat, then add 1/4 cup of the reserved pasta cooking water, stirring to incorporate. Cook over low heat for 2 minutes, stirring and adding some or all the remaining pasta cooking water, as needed, to achieve the sauce consistency you prefer.

Source: Washington Post January 04, 2019 18:00 UTC