Ingredients

• 2 ½ cups chicken stock
• ¼ cup dry white wine
• 2 tablespoons tomato paste
• 1 (28-ounce) can crushed tomatoes, preferably fire-roasted
• 1 tablespoon balsamic vinegar, preferably aged
• 6 garlic cloves, finely chopped
• 2 tablespoons chopped fresh oregano (from about 3 to 4 sprigs) or 1 1/2 teaspoons dried oregano
• 2 teaspoons onion powder
• ½ teaspoon red-pepper flakes
• ½ teaspoon kosher salt, plus more as needed
• 1 ¾ to 2 pounds boneless, skinless chicken thighs
• 5 ounces baby spinach
• 1 (8- to 10-ounce) package refrigerated cheese tortellini
• 1 cup grated Parmesan, for serving
• Torn or sliced fresh basil, for serving
• Black pepper, for serving

Steps

1. In a 6- to 8-quart slow cooker, whisk together the stock, wine and tomato paste until the paste dissolves. Stir in the tomatoes, vinegar, garlic, oregano, onion powder, red-pepper flakes and salt. (If you are using unsalted stock, add an additional 1/2 teaspoon salt.) Add the chicken and stir to combine. Cook on low until the chicken is very tender and the flavors are blended, 5 to 6 hours.
2. Increase the heat to high for 10 minutes. Coarsely shred the chicken with two forks, pressing pieces of chicken against the side of the slow cooker to break the thighs apart. Stir in the spinach so that it wilts into the soup.
3. Stir in the tortellini, cover the slow cooker, and cook until the tortellini are al dente and warmed through, about 3 minutes. Taste the soup and add salt if it tastes flat. Ladle the soup into bowls and serve with Parmesan, basil and black pepper.