In a large stock pot, heat the olive oil over medium heat. Add in the red pepper flake and sauté for a minute or two.
Add in the hot Italian Sausage and cook through. Remove Italian Sausage and set aside.
Add in the chopped onion, carrots, and celery and continue sautéing until the veggies are tender, about 5-7 minutes.
Stir in garlic and cook for 30 to 60 seconds.
*Optional - stir in 1 tablespoon double concentrated tomato paste.
Pour in the chicken broth and diced tomatoes.
Add in Italian Seasoning, salt, and black pepper. Bring to a boil.
When the soup is boiling, add in the tortellini and cook according to package directions (typically 3-7 minutes, depending on whether or not the tortellini is fresh or frozen).
Reduce the heat to low and stir in the heavy cream and finely grated parmesan cheese.
Stir in chopped kale.
Allow the soup to simmer for a few minutes longer.
Adjust seasonings to taste.
Serve with additional fresh parmesan cheese for garnish.