Cannelloni, meaning "large reeds" in Italian, are usually large sheets of pasta rolled around stuffing and then baked. After World War II, the shape became very famous in the US as Manicotti. Each box contains 20 Cannelloni.
Do not par boil. Simply stuff the pasta with your desired stuffing, cover with Béchamel sauce or tomato sauce and bake for 40 minutes at 400° F.