From the blog For Love of the Table
2 T. Olive oil
2 oz. pancetta, finely diced
1 leek, white and pale green only, halved and cut in 1/3-inch dice and thoroughly rinsed in several changes of water
1 small onion (4 to 6 oz.), cut in ¼-inch dice
2 medium stalks celery, trimmed and cut in ¼-inch dice
1 large carrot, peeled and cut in ¼-inch dice
Salt & freshly ground pepper, to taste
3 cloves garlic, peeled and minced
2 to 3 t. double concentrate tomato paste
6 to 8 cups water, or chicken/vegetable stock or a mixture
1 c. farro, preferably semi-pearled, but pearled may also be used—rinsed
2 bunches Tuscan Kale, stems stripped away, leaves cut in 1/2-inch wide ribbons and thoroughly rinsed
Parmesan and Olive oil for serving
Heat the olive oil in a large soup pot set over medium heat. Add the pancetta and cook until fat is mostly rendered—3 minutes or so. Add the leek, onion, celery and carrot along with some salt and freshly ground pepper. Cook until the vegetables are wilted and beginning to soften—about 5 to 7 minutes. Add the garlic and cook for another minute. Whisk the tomato paste into 1 cup of water and add. Bring to a simmer and cook until all of the liquid has evaporated—about 20 minutes. Add another 5 cups of water (or stock), the farro and the kale. Bring to a simmer (the kale will collapse to the level of the liquid within a few minutes) and cook, stirring occasionally, until the farro and kale are both tender and the flavors of the soup are blended—about 25 to 40 minutes. If, at any time after the kale collapses, the soup seems too crowded, add more water and continue to cook. When the farro and kale are tender, taste and correct the seasoning with salt and pepper. Serve with a drizzle of olive oil and some freshly shaved or grated Parmesan cheese.
Makes about 2 quarts of soup, serving 4 to 6.
(Recipe adapted from Olives & Oranges by Sara Jenkins & Mindy Fox)
Notes & Variations:
• If you have any rinds of Parmesan in your cheese drawer, add them to the soup with the farro and kale. They add wonderful flavor. Remove the rinds before serving the soup.
• If you prefer, you may add some canned tomatoes to the soup instead of the concentrated tomato paste in water. Run the tomatoes through a food mill fitted with a fine disc, or purée them in the food processor. Add, thinning with a bit of water if you like, and cook until reduced and very thick before proceeding with the recipe. For this size batch of soup, use anywhere from half to a full 14-oz. can of Italian plum tomatoes.
• To prepare a vegetarian soup, omit the pancetta and increase the olive oil to 3 to 4 T. Use water for the liquid.
• Some diced, peeled potatoes or cooked white beans (with their cooking liquid) may also be added to the soup. Add with the farro and kale.
• If semi-pearled (or pearled) farro is not available, you may use whole farro, but since it takes much longer to cook, it should be cooked separately and added to the soup when the kale is almost tender.
http://www.forloveofthetable.com/2011/01/my-introduction-to-farro-in-farro.html