Fish soup is popular in both islands and, though there is a standard recipe, each cook adds his or her special touch. M. Mario Petreluzzi, the moving spirit of La Pergola Restaurant at Gosier, in Guadeloupe, used to add a dash of Ricard to his soup. And the cooks at the Bakoua Hotel at Trois Ilets in Martinique, add croûtons and grated Gruyère cheese to theirs. In both cases with admirable results.