It's hard to know what came first at Ukyo - the sake or the truffle. Although most refer to Ukyo as a sake bar or izakaya, lately it has become known as the sweet spot for the truffle hunters of Tokyo. In contrast to Tokyo's typical izakaya scene with its cheap beer, skewers of inexpensive meats and traditional small plates, Ukyo is an experience that is all about modern decadence.  Boasting a selection of over 200 sakes, the highly customized experience begins with choosing your own, personal sake glass. Skimming through the menu you will notice that Ukyo has every indulgent item imaginable - caviar, uni, foie gras, stinky european cheeses. But it's the truffle that gets all the glory. Ukyo imports massive quantities of truffle from Italy every year (we're talking human body size) in order to shave generous (some say, gluttonous) amounts of the black gold onto, well, everything. Ukyo's bartenders will help you select find the perfect pairing. Top-shelf sake sluts will lust over names like Raifaku, the highest polished sake in Japan, or Jokigen, sake stored in white wine barrels from Napa.  As you've probably guessed, this is a hot spot even 5 years after opening (no easy feat in a gastronomically fickle city such as Tokyo) so reservations are a must, even for the bar. The space is expectedly tight with more than half of its 30 seats dedicated to the bar. But if you planned poorly, it is possible to score a walk-in seat if you get very, very lucky.  Whether you're here for the sake or the truffles, it's really a win-win situation.