Ingredients

• 6 tablespoons olive oil, divided

• 1 pound boneless, skinless chicken thighs

• 1/2 teaspoon black pepper

• 2 1/2 teaspoons kosher salt, divided

• 2 cups chopped yellow onion (from 1 large onion)

• 1 cup chopped celery (from 2 stalks)

• 5 garlic cloves, chopped (about 2 tablespoons)

• 1/4 cup fresh basil leaves, plus more for garnish

• 1/2 cup dry white wine

• 1 tablespoon tomato paste

• 4 cups unsalted chicken stock

• 1 (28-ounce) can whole peeled tomatoes, drained

• 4 cups stemmed and thinly sliced lacinato kale (from 1 bunch)

• 1 (8-ounce) package refrigerated cheese tortellini

• 2 ounces Parmesan cheese, grated (about 1/2 cup)