- 2 cups Great Northern beans—picked over, soaked overnight and drained
- Kosher salt
- 1 1/2 cups farro (9 ounces)
- 1/2 cup Arbosana extra-virgin olive oil
- 1 large Spanish onion, halved and thinly sliced
- 1 1/4 cups thinly sliced carrots
- 1 1/4 cups thinly sliced celery root
- 1/3 cup thinly sliced garlic
- Two 28-ounce cans fire-roasted diced tomatoes
- 1 pound red Swiss chard, stemmed and leaves chopped
- 2 tablespoons minced parsley
- 1 tablespoon minced rosemary
- 1 tablespoon minced thyme
- 1 tablespoon minced oregano
- 1/2 jalapeño, seeded and minced
- 1 1/2 teaspoons finely grated lemon zest
- 1 cup Arbosana extra-virgin olive oil
- Kosher salt
- Freshly grated Parmigiano-Reggiano cheese, for serving
- In a large pot, cover the soaked beans with water (at least 4 inches) and bring to a boil. Simmer over moderately low heat until the beans are tender, about 1 hour and 15 minutes. Add 1 tablespoon of salt and let stand for 5 minutes. Drain, reserving 6 cups of the cooking liquid.
- Meanwhile, in a medium saucepan of salted boiling water, cook the farro until al dente, about 20 minutes. Drain.
- Wipe out the large pot and heat the olive oil in it. Add the onion and a generous pinch of salt and cook over moderate heat, stirring occasionally, until softened but not browned, about 7 minutes. Add the carrots, celery root, and garlic and cook, stirring occasionally, until the vegetables just start to soften, about 5 minutes. Add the tomatoes with their juices and cook over moderately high heat, stirring occasionally, until the juices have reduced by half, 8 to 10 minutes.
- Add the reserved bean cooking liquid and 14 cups of water to the pot and bring to a simmer. Stir in the beans, farro and Swiss chard and simmer over moderate heat until the chard is wilted and the soup is hot about 5 minutes. Season with salt and pepper.
For the herb oil:
- In a medium bowl, whisk the herbs with the jalapeño, lemon zest and olive oil; season with salt.
- To serve, ladle the soup into bowls and top with the herb oil and cheese.