Like most teenagers coming of age, all Marianna Leivaditaki wanted to do was escape her surroundings. That meant getting off the Greek island of Crete. With a fisherman father and a mother who ran the family restaurant, chores ranged from hanging octopus off the clothesline to gutting fish and setting tables. And while she is head chef of Morito in London, the recipes and ingredients of her youth inform her first cookbook, “Aegean.”