In east London’s Hackney Wick  beside the craft breweries  graffiti-clad warehouses and canal boats  chef Mr Tom Brown is cooking some of the capital’s finest seafood The concise menu at his debut restaurant  Cornerstone  is made up of simple dishes – pickled oysters with horseradish  celery and dill  baked scallops with coral butter and lime  or cured gurnard with grapes  almond and sherry vinegar – which demonstrate a respect for impeccable-quality  carefully sourced fish and shellfish  prepared without fuss