In a large pot over medium-high heat, brown the turkey sausage, breaking it into small pieces with a spatula or wooden spoon. Add onions and sauté until the onions start to become translucent.
Add diced tomatoes and tomato paste, and bring to a boil. Meanwhile, chop up celery and carrots, and add to the pot.
Add the chicken broth and stir in the garlic powder, salt, and pepper. Bring the soup back to a boil, then reduce the heat and simmer for at least an hour.
After simmering, add the heavy cream (optional), then increase the heat and bring the soup back to a low boil. Stir in the chopped spinach, then add the tortellini and boil until the pasta is just cooked.
Top with Parmesan and enjoy!
