Penne with Ricotta and Asparagus

1 Bring a large pot of salted water to a boil, add the asparagus and cook until tender.
2 Using tongs, transfer the asparagus to a bowl, and then drain well in a colander.
3 Cut off and reserve the asparagus tips: roughly chop the stems.
4 In a blender, puree the asparagus stems, ricotta and a dash of salt, until smooth. Taste and add more salt if desired.
5 Return water to a boil and cook the pasta until al dente. Reserve serving ½ cup of the pasta cooking water, drain pasta and transfer to a large serving bowl.
6 Immediately toss with ricotta mixture, and then add Parmigiano and prosciutto.
7 Toss to combine. Moisten with pasta cooking liquid if desired. Garnish with reserved asparagus tips and serve immediately.