The last time I walked the entrails of Delhi’s old city, I came across raw potato chaat, beef biriyani with pickle and the fabled makkhan , but also something else that I only discovered later to be quite a find. That last time, my pocket was full of fresh, atm-expelled five hundred rupee notes which when hunting for street food is a disturbing proposition. I was therefore looking for a way to buy just below a hundred rupees worth of something, so that it would lead to oodles of change. At eight in the evening, there wasn’t that much open in Bazaar Sitaram, but one store displayed stacks of vadis and a friendly shopkeeper willing to give directions, so I bought some eighty rupees worth. Those, I discovered a week later when one of them hit my tongue, was the discovery of the journey. Forget the sheermals and raw aloochaat – this was the best vadi I’d ever had, and frankly one of the best foods I’ve ever bought by accident. A few weeks later, finding myself near the metro line in Delh...