Zuppa Toscana (Tuscan soup) comes together in one pot with straightforward steps and familiar ingredients. Browning the sausage and bacon first builds flavor, while the potatoes and cream create a naturally thick, comforting broth.
In a Dutch Oven or large stock pot over medium-high heat, cook ground Italian sausage, bacon, and onion until browned, stirring occasionally, about 7-10 minutes. Drain well.
Add garlic and cook until fragrant, about 30 seconds. Add broth and the bay leaf, scraping the bottom of the pot to pull up any browned bits. Bring to a boil. Add the potatoes and simmer until tender, about 10 minutes. Skim off fat as needed.
Stir in kale and heavy cream and continue to cook 2 to 3 minutes more (do not boil). Discard bay leaf. Add red chili flakes (if using) and season to taste with salt and freshly ground black pepper (I like 1/2 teaspoon salt and 1/4 teaspoon pepper). Serve topped with freshly grated Parmesan cheese.
Notes
Sausage: To substitute links, slice them open and scrape out the bulk sausage inside.
Potatoes: For thick and creamy soup, use high-starch russet potatoes. If you like a chunky soup with a little more texture, use Yukon Gold potatoes, which hold their shape better.