And then there is the most self-indulgent truffle recipe of all, which a friend claims is the closest thing on earth to having heaven in your mouth. You start with a generous slice of foie gras, and place it on a sheet of tinfoil. You then place your truffle on the foie gras and put it in the oven, where the truffle gradually sinks into the melting foie gras. The complex, slightly earthy taste of the truffle and the unctuous coating of foie gras may put you off hamburgers forever. Bon appetit!