Slice the pancetta in small pieces. Crumble the pistachios coarsly with a knife.
Wilt the onion in a saucepan with a drizzle of extra virgin olive oil.
When the oil is hot, add the diced pancetta and brown it quickly, for a few seconds.
Add the cream, the pistachios and a couple of shaves of Piave DOP Vecchio cheese.
Cook on low heat until the sauce has thickened slightly.
Put the paccheri pasta in a big pot of salted boiling water.
Check the cooking time on the package, and boil it for 1 minute less than indicated.
Drain the pasta, keeping half a glass of the cooking water.
Put the pasta in the skillet with the sauce and cook together for a couple of minutes on low heat.
If the sauce is too thick, add some of the cooking water and turn off the heat.
Serve the pasta on individual plates, shaving some Piave Vecchio DOP cheese before serving.
Serve immediately