In a large pot or Dutch oven, heat a drizzle of olive oil over medium heat. Add the Italian sausage, breaking it apart and cook for about 5–7 minutes until browned and crispy.

Add the diced onion and sauté for 3–4 minutes until soft. Stir in the minced garlic and cook for another minute.

Stir in the diced potatoes, then pour in the chicken broth. Bring to a boil, then reduce to a simmer for about 15 minutes until potatoes are tender.

Fold in the chopped kale along with red pepper flakes, if using, and cook for an additional 5 minutes.

Reduce heat to low and stir in the heavy cream. Season with salt and pepper to taste and warm through for another 2–3 minutes.

Ladle the soup into warm bowls and serve hot, preferably with crusty bread.