Taking its name from a peculiar species of tusked Arctic whale that survives the pitch-black depths of upto (or rather down to) 1500 metres, Narwhal Imperial Stout from California’s Sierra Nevada Brewing Co is a deliciously dark, tremendously rich and unbelievably complex Russian Imperial Stout. Pouring into the suggested ‘snifter’ glass a thick, viscous oil-slick black with a head reminiscent of a perfect espresso coffee shot, this is a beer that grabbed my attention from the outset – it actually looked like it was going to be well worth drinking…