In a large pot, heat olive oil over medium heat, then add the Italian sausage. Cook until browned, around 8-10 minutes. Drain excess grease if necessary for a lighter soup.

Sauté diced onion and minced garlic in the pot for 2-3 minutes, until fragrant. Then, stir in chopped banana peppers and cook until tender, about 5 minutes.

Pour in chicken broth, stirring to combine. Bring the mixture to a low boil, then reduce the heat and let it simmer for 20 minutes.

Gradually stir in cream cheese, mozzarella, and cheddar cheese until fully melted and smooth.

Slowly mix in heavy cream, stirring frequently. Let the soup simmer gently for another 5-10 minutes.

Taste and season with salt and pepper as desired. For an extra-smooth texture, blend half of the soup with an immersion blender, if you like.

Ladle the creamy goodness into warm bowls. Garnish with additional cheese or fresh parsley and serve with crusty bread or croutons.