Preparation Wash leek greens well in a bowl of cold water, then lift out and drain well. Tuck bay leaves and herb sprigs into leek greens and tie tightly in a bundle with string to make a bouquet garni. Bring water, bouquet garni, onion, and chile to a boil in a 5-quart heavy pot and simmer, partially covered, 20 minutes. Add beans and simmer gently, stirring occasionally and adding 1 tablespoon kosher salt toward end of cooking, until tender, about 25 minutes for fresh beans or 50 minutes to 1 1/4 hours for soaked dried. Discard bouquet garni, and discard onion and chile if desired. Just before serving, transfer beans with a slotted spoon to a dish and season with kosher salt. Drizzle with oil and sprinkle with mint and thyme. Cooks' note:
Preparation Wash leek greens well in a bowl of cold water, then lift out and drain well. Tuck bay leaves and herb sprigs into leek greens and tie tightly in a bundle with string to make a bouquet garni. Bring water, bouquet garni, onion, and chile to a boil in a 5-quart heavy pot and simmer, partially covered, 20 minutes. Add beans and simmer gently, stirring occasionally and adding 1 tablespoon kosher salt toward end of cooking, until tender, about 25 minutes for fresh beans or 50 minutes to 1 1/4 hours for soaked dried. Discard bouquet garni, and discard onion and chile if desired. Just before serving, transfer beans with a slotted spoon to a dish and season with kosher salt. Drizzle with oil and sprinkle with mint and thyme. Cooks' note: