Up a flight of rickety stairs in Hanoi is a 100-year-old restaurant that is often a must-not-miss in guidebooks It serves one iconic, delicious dish, called cha ca la Vong, which also happens to be the name of the restaurant In the bright, noisy dining room, packed with communal tables set with little charcoal burners, a skillet of fish and other components arrives, and you submit to a brusque ceremony of tabletop cooking and do-it-yourself assembly