As autumn’s chilly winds sweep through the Vietnamese capital, anticipation grows among Hanoi’s foodies for a rare, slithering delicacy, one that’s unsuitable for the squeamish: fried worm omelettes.At a street-side stall in Hanoi’s hectic Old Quarter, a tourist hotspot famous for markets and eateries dotted along ancient streets, strangers sit shoulder-to-shoulder on tiny plastic stools. Inches from buzzing motorbikes and only a few metres from an ancient gate to the city, the experience of sitting here is already intimate and exhilarating.And then you see the worms.Beneath the restaurant’s m…