2 tablespoons olive oil

8 ounces (225 g) loose Italian sausage

2 onions (12 oz/ 340 g), chopped (about 2 cups)

1 teaspoon dried oregano

1 teaspoon fennel seeds

Kosher salt and freshly ground black pepper

2 Yukon Gold potatoes (1 lb/455 g), cut into I-inch (2.5-

cm) pieces

8 cups (2 L) chicken stock from Whole Poached Chicken

, or Vegetable Stock

1 bay leaf (optional)

1 (15.5-oz/43 9-g) can cannellini beans, rinsed

1 large bunch kale (about 1 lb/455g), stemmed and leaves

torn

2 tablespoons red wine vinegar

Grated Parmesan cheese, for serving

Heat the oil in a large pot over medium-high heat. Add

the sausage and break it up with a wooden spoon so it's

in small, bite-size pieces. Don't touch the pieces for 2 to 3

minutes, until golden brown on the bottom. Using tongs,

flip the sausage pieces over and leave them until cooked

through and golden brown on all sides, 2 to 3 minutes

more.

Transfer the sausage to a paper towel—lined plate,

leaving the fat and oil behind in the pan. Cover the

sausage with aluminum foil to keep in any moisture and

set aside.

Return the pot to medium heat and add the onions,

oregano, fennel seeds, 2 teaspoons salt, and 1 teaspoon

pepper. Cook, stirring often, until the onions are

translucent and soft, 10 to 12 minutes. Add the potatoes,

stock, and bay leaf (if using). Cover and bring to a boil

over high heat, then reduce to a gentle simmer and cook

until the potatoes are fork-tender, 8 to 10 minutes.

Stir in the beans, kale, and reserved sausage. Cook until

the beans are heated through. Fish out the bay leaf, stir

in the vinegar, and taste and adjust the seasoning with

more salt and pepper if you want.

Serve the soup hot with a pile of freshly grated cheese

on top.