Chestnut and Kale Soup
Zuppa di Castagne e Cavolo Nero

Cavolo nero is a member of the kale family. Between farm stands, specialty produce 
markets, and natural foods stores it is available year-round. To find it, be aware 
of its many aliases: Tuscan kale, black cabbage, lacinato, and dinosaur kale. 
Its rich, sweet, almost meaty flavor will have you hooked from the first bite.

Ingredients
1/2 pound dried white beans such as cannellini, Great Northern, 
or navy (about 1 1/4 cups), picked over and rinsed
1/4 pound thinly sliced pancetta, chopped
1 large onion, chopped
3 garlic cloves, finely chopped
3 tablespoons extra-virgin olive oil
1 (14-ounce) can whole tomatoes in juice, drained, reserving juice, and chopped
3 1/2 cups low-sodium chicken broth (28 fluid ounces)
2 cups water
1 piece Parmigiano-Reggiano rind (roughly 3 by 2 by 1/2 inch)
1 1/2 teaspoons salt
1/4 teaspoon black pepper
1 1/2 cups bottled peeled cooked whole chestnuts (8 ounces), halved
1/2 pound cavolo nero or regular green kale, stems and center ribs discarded 
and leaves torn into bite-size pieces
2 teaspoons chopped fresh thyme
Accompaniment: grated Parmigiano-Reggiano
Garnish: Parmigiano-Reggiano shavings; extra-virgin olive oil for drizzling; 
black pepper; fresh thyme sprigs; whole chestnuts

Preparation
1. Soak beans in cold water to cover by 2 inches in a bowl at room temperature at 
least 8 hours, or quick-soak (see cooks' note, below). Drain well in a colander. 
2. Cook pancetta, onion, and garlic in oil in a wide 6- to 8-quart heavy pot over 
moderate heat, stirring occasionally, until browned, about 8 minutes. Add tomatoes 
with juice, beans, broth, water, cheese rind, salt, and pepper and simmer, uncovered, 
until beans are tender, 45 minutes to 1 hour. Discard cheese rind and stir in chestnuts. 
3. Transfer 2 cups soup to a blender and purée until smooth (use caution when 
blending hot liquids), then return to pot. Stir in kale and simmer, uncovered,
stirring occasionally, until leaves are tender, 10 to 15 minutes. Stir in thyme. 

Cooks' notes:
1. Soup can be made 3 days ahead and cooled completely, 
uncovered, then chilled, covered. Reheat, thinning with water as necessary.
2. Beans can be soaked at room temperature up to 12 hours.
3.·To quick-soak beans: Cover beans with cold water by 2 inches 
in a 4- to 5-quart pot and bring to a boil, uncovered. 
Boil beans 2 minutes, then remove from heat and let stand, uncovered, 1 hour.