Louis-Bernard Puech, known to friends and relations as Loulou, is nothing if not persistent. When he was studying at the Toulouse Ecole Hôtelière in the early seventies, he decided that he wanted to work with the great Lucien Vanel, then owner-chef of the city’s most highly regarded restaurant. So one day the young Loulou dropped in on Vanel and asked him if by any chance he needed anyone to help him out in the kitchen. Vanel, in the best boorish tradition of top chefs, thr