Boil pasta in salted water until al dente.
In a separate saucepan at the same time, boil the cashews.
While they are cooking, gather the other sauce ingredients.
When the pasta is done, drain and reserve 1/4 cup pasta cooking water.
Drain cashews, add them to a blender along with remaining sauce ingredients. Add sauce back to hot pasta.
Stir well, add bit of pasta water a little at a time if desired, to thin the sauce.
Serve, top with chives and paprika or cayenne.