Creating an amazing Zuppa Toscana is straightforward if you follow these steps:

1. Cook the Sausage: In a large pot, heat the olive oil over medium heat. Add the Italian sausage, breaking it apart with a spoon. Cook until browned and no longer pink, about 5-7 minutes.
2. Add Onions and Garlic: Stir in the diced onion and minced garlic. Sauté until the onion is translucent, around 3-4 minutes.
3. Add Broth and Potatoes: Pour in the chicken broth and add the sliced potatoes. Bring to a boil, then reduce heat and let it simmer for about 10-12 minutes, or until the potatoes are tender.
4. Incorporate Kale: Once the potatoes are done, add the chopped kale. Stir and let it cook for another 2-3 minutes until wilted.
5. Pour in Cream: Lower the heat and stir in the heavy cream. Ensure everything is well combined. Season with salt, pepper, and red pepper flakes if using.
6. Simmer: Allow the soup to simmer for an additional 5 minutes, allowing the flavors to meld together.
7. Taste and Adjust Seasoning: Before serving, taste the soup and adjust the seasoning as needed.

Following these steps will lead you to an incredible bowl of Zuppa Toscana that satisfies and delights.