In Vengeance Tastes Sweet, the second in the Wally Morris murder series, Beverly Cohen, a local caterer with big aspirations, doesn't care whose toes she steps on in her quest for success. Her ability to insult people is matched only by her insensitivity to their feelings. Although her constant bragging is annoying, it is her indiscrete remarks to a tabloid reporter that could ruin someone's life. <P> Not surprisingly, someone poisons her. <P> Wally Morris, who has witnessed Beverly's vitriol and boasts, investigates the murder after she decides that the wrong person has been arrested. The suspects range from residents of Wally's town of Grosvenor, New Jersey, to movie stars working on the film being made in town. <P> It will take all of Wally's perspicacity and keen powers of observation to solve the case. But if she finds the killer, will she have to pay for her inquisitiveness with her life?