Rao's CookbookBy: Frank Pellegrino Raos, the hundred year old restaurant with a mere ten tables tucked in a corner of East Harlem in what was once a legendary Italian neighborhood, is one of the most sought after restaurants in all of Manhattan. Its tables are booked months in advance by regulars who go to enjoy what The New York Times calls its exquisitely simple Italian cooking from traditional recipes, many as old as Raos itself. You may not get a table at Raos,