Brown the sausage: In a large pot over medium heat, add the sausage. Cook until browned, breaking it apart as it cooks for about 5-7 minutes.
Saute onion and garlic: Stir in the chopped onion and garlic, cooking for an additional 3-4 minutes until the onion is translucent and fragrant.
Add potatoes: Next, add the diced potatoes to the pot along with the chicken broth. Bring to a boil, then reduce the heat and let simmer for about 15 minutes, or until the potatoes are fork-tender.
Incorporate the greens: Add in the kale or spinach and let it wilt down into the soup for about 2-3 minutes.
Make it creamy: Stir in the heavy cream or your preferred substitute, allowing it to heat through for another 2-3 minutes.
Season to taste: Taste the soup and add salt and pepper as needed.
Serve warm: Ladle into bowls and enjoy your delicious Easy One Pot Zuppa Toscana!