Very few things remind me of winter like chestnuts do. During Christmas in Rome, you see chestnut vendors everywhere, with their huge portable barbecues, wrapping the roasted wonders in paper to sell. Walking around the city eating them, with their aroma all around, looking at decorated Christmas trees in every square, kids singing carols on church corners, Piazza Navona with its market and lights, and a glass of mulled wine in one of the cafés around, is quintessential Roman Christmas for me. Many cafés serve chestnut cake of all kinds, but the one I truly adore is this tart. I tried it a long time ago in the famous Caffè Greco, off the Spanish Steps, and since then it has become one of my alltime favourite Christmas treats. You can decorate it with holly, glazed cranberries or simply leave it as it is.