Preheat oven to 350°F.

Toss coarsely torn sourdough bread with 3 tablespoons olive oil on a rimmed baking sheet.

Season with kosher salt.

Squeeze bread to moisten.

Toast in the preheated oven, tossing occasionally, until golden brown and crunchy, 15-18 minutes.

Let croutons cool.

Mix sweet Italian sausage (casings removed) and dry white wine in a medium bowl until smooth.

Cook sausage mixture in a large saucepan over medium heat, stirring occasionally, until firm but not browned, about 4 minutes.

Add finely chopped onion, carrots, celery, anchovy fillets (drained, chopped), thinly sliced garlic cloves, and 1 teaspoon crushed red pepper flakes.

Cook, stirring occasionally, until vegetables are tender but still hold their shape, 20-25 minutes.

Add torn Tuscan kale (ribs removed), finely chopped whole peeled tomatoes (drained), rinsed cannellini (white kidney) beans, and low-sodium chicken broth and bring to a boil.

Reduce heat and simmer, stirring occasionally, until kale offers no resistance when bitten and flavors have melded, about 1 hour.

Just before serving, add red wine vinegar and half of the croutons to the soup, stirring to break them into smaller pieces.

Divide remaining croutons among bowls.

Ladle soup over croutons.

Serve topped with shaved Parmesan and drizzled with more olive oil.