Now in its fifth decade, having passed its 40th in style, Le Gavroche has occupied its current Upper Brook Street premises since 1981. Chef Michel Roux Jr has updated the classic haute French cooking of his uncle and his father, while paying tribute to it, since he took over in a 1991. Dishes, such as lobster mousse with caviar and champagne sauce, are lighter than they would have been a generation ago but remain luxuriant. You no longer need to wear a tie but a jacket is always required. The service, forged under the direction of Silvano Giraldi, who recently retired after 37 years, is spectacularly smooth. Of course it’s expensive but the £48 set lunch is exceptionally good value. As Fay Maschler, restaurant critic of The Evening Standard, says about anyone you take there, “If they aren’t impressed, ditch them.”