01 -
Bring a large pot of water to a boil and salt it lightly. Cook penne according to the packet until al dente, adding frozen peas for the final 2 minutes.
02 -
Before draining, reserve 300 ml pasta cooking water in a heatproof jug. Drain the pasta and peas.
03 -
In a large bowl, whisk ricotta, Parmesan, olive oil, lemon zest, lemon juice, pepper and the measured salt. Whisk in 100 ml hot pasta water until creamy.
04 -
Add the hot pasta and peas to the bowl. Toss thoroughly, adding more reserved water a little at a time until the sauce coats the pasta without pooling. You may not need all the water.
05 -
Fold in basil and serve immediately. The sauce thickens as it stands; loosen with a little warm water if needed. Do not boil the ricotta sauce.
06 -
Refrigerate leftovers within two hours in a sealed container for up to two days. Reheat gently with a splash of water until hot throughout.