Like many of Mumbai's office workers, Mr Roy eats lunch food prepared for him by his wife while it is still fresh and hot.

We venture to a major market in the Qing Yang district, where we snack on sweet-potato noodles and fresh spring rolls before browsing the market's many offerings.

Finally, it was time to go back down the hill and across the stream to the trailer, where her husband came through the door with a surprise: freshly baked rolls, still warm from the oven.