In a large saucepan, cook the Italian sausage and chopped onion until the sausage is browned. Ensure to break it apart while cooking. Drain excess fat.

Add minced garlic, fennel, and red pepper flakes to the pan and cook for about a minute until fragrant.

Pour in the chicken broth, diced tomatoes, pasta, and Italian seasoning. Bring the mixture to a boil, then reduce heat and let it simmer until pasta is al dente, about 6 to 8 minutes.

Stir in grated parmesan, cream cheese, and heavy cream. Allow the cheese to melt into the soup for about 3 to 5 minutes.

Season with salt and pepper to taste, mix in chopped parsley, and enjoy your warm bowl of soup!