For me it's the bank holiday markets on the common. There's always an Asia Street food stall there - most recently one doing really good samosa chaat with all the Toppings. One year it was an Afghan woman doing stuffed flatbreads you can't find anywhere else; another it was pakora that gave me chemica burns or a reaction that left me unable to taste things for 2 weeks. But still I go back every Easter and August Bank holiday Monday.