Houstonist headed out to Washington Avenue this past Sunday afternoon to try the newest Italian restaurant cum grocery store, Raia's Italian Market. With an untested location in a brand-new building and the time-tested juggernaut Nundini's only a few blocks away, it would appear that Raia's has a lot to overcome if it wishes to succeed in a market already saturated with Italian restaurants (Candelari's, Spaghetti Western, Star Pizza, Collina's, Patronella's, and Cavatore are just......