In a large pot, warm a generous drizzle of olive oil over medium heat. Once the oil is shimmering, add the diced onion and sauté until it becomes translucent, approximately 3-4 minutes.
Stir in the minced garlic and sauté for another minute, ensuring to stir constantly to prevent the garlic from burning and becoming bitter.
Crumble the Italian sausage directly into the pot, breaking it up with a spatula as you cook. Allow it to brown completely and lose its pink color, which should take about 5-7 minutes.
Carefully pour in the chicken broth and bring the mixture to a gentle boil. Once boiling, add the thinly sliced potatoes and cook until they are fork-tender, generally about 10-12 minutes.
Stir in the chopped kale and continue to simmer for an additional 5 minutes, or until the kale has wilted but retains its vibrant color.
Lower the heat to a gentle simmer and incorporate the heavy cream. If you’re opting for extra spice, add the red pepper flakes at this stage. Season with salt and pepper to taste, giving it a good stir to combine.
Allow the soup to gently heat through, ensuring it doesn’t boil after adding the cream to keep it rich and creamy.
Serve the Zuppa Toscana hot, garnished with grated Parmesan cheese, if desired, for that extra layer of flavor and elegance.
Notes
Use low-sodium broth for better control of saltiness. Coconut cream can be used for a dairy-free option.