YOU cannot BRIE serious - the world's most expensive cheese sandwich costs a whopping $2. But hungry punters will have to Caerphilly plan their expedition to the exclusive Serendipity 3 in New York City - as the sandwich needs to be ordered 48 hours in advance. For the grate-ing price tag cheese lovers receive a 23-carat gold edged grilled cheese sandwich with lobster bisque served in a baccarat crystal glass. But it gets Feta - the bread is baked using Dom Perignon Champagne and brushed with truffle oil that contains flecks of edible gold. It is then layered with grass-fed white truffle butter before slices of the extremely rare Caciocavallo Podolico cheese - which is aged in caves - are added.