An overhead view of the Grand Tier restaurant. Photo courtesy of the Grand Tier | The Grand Tier There are two places where a restaurant like the Grand Tier could exist: inside a snowglobe, or inside New York City’s Metropolitan Opera . Luckily, it has been housed in the latter — encased in some 45,000 feet of glass, no less — for the past 60 years, where it offers hungry opera-goers a surreal experience. I have never before, for example, eaten a crab cake while locking eyes with a flying goat in a 30-foot tall Chagall painting , nor have I ended dinner with the trill of a glockenspiel, reminding me that it’s time to finish my dessert and watch Madame Butterfly confront her cheating husband.  For the general manager George Krpeyan, that’s just another Tuesday night.…