One of the most spectacular ways to serve pasta is al cartoccio--boiled, sauced, then wrapped in parchment paper (or aluminum foil) and baked. This might sound like an odd preparation method, but your guests will greet the arrival of the packets at the table with mounting anticipation that will turn to joy as they open them. This traditional italian recipe calls for a variety of shellfish, many of which are strictly mediterranean and difficult to find outside of that area. This updated version omits the more obscure shellfish. If the shells of the shellfish (clams, etc. ) are pretty, scrub them very well before you begin making the sauce, and don't shuck them after they have opened: put them--shells and all--in the cartoccio and they'll add a special touch to the finished dish. [edited by danette st. Onge].