Sausage, Cannellini and Kale Soup

This hearty Tuscan soup is full of flavor. The crinkly, deep-green leaves of Lacinato kale (also called dinosaur or black kale) are ideal, but any variety of kale will work.
This recipe is easily adaptable to serve meat-lovers and vegetarians alike: see the variation to serve one vegetarian, or check out the totally meatless version of this recipe.

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  1-1/2 Tbs. extra-virgin olive oil
  
  


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  1 medium yellow onion, finely chopped (1-1/2 cups)
  
  


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  1 medium carrot, peeled and finely chopped (3/4 cup)
  
  


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  1 medium celery stalk, finely chopped (3/4 cup)
  
  


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  1-1/2 tsp. minced fresh rosemary
  
  


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  2 Tbs. tomato paste
  
  


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  2 large cloves garlic, minced (1 Tbs.)
  
  


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  1 quart homemade or lower-salt chicken or vegetable broth
  
  


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  Two 15-oz. cans cannellini beans, rinsed and drained
  
  


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  6 oz. Lacinato kale, center ribs removed, leaves chopped (about 4 firmly packed cups)
  
  


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  1 Parmigiano-Reggiano rind (1x3 inches; optional)
  
  


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  1-1/2 tsp. cider vinegar
  
  


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  Kosher salt and freshly ground black pepper
  
  


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  2/3 lb. sweet or hot bulk Italian sausage, rolled into bite-size meatballs
  
  

Heat 1 Tbs. of the oil in a 4- to 5-quart pot over medium heat. Add the onion, carrot, celery, and rosemary and cook, stirring occasionally, until the vegetables begin to soften, about 6 minutes. Add the tomato paste and garlic and cook until fragrant, 45 seconds. Add the broth, beans, kale, and Parmigiano rind (if using). Bring to a boil, reduce the heat to medium low, and simmer gently until the vegetables are tender, about 15 minutes.


Meanwhile, heat the remaining 1/2 Tbs. oil in a 10-inch nonstick skillet over medium-low heat. Add the sausage meatballs, sprinkle with a pinch of salt, and cook, stirring occasionally, until browned and cooked through, about 10 minutes.


Add the sausage to the soup and bring to a simmer over medium-high heat. Cook 5 minutes more to meld the flavors. Stir the cider vinegar into the soup and season to taste with salt and pepper.