Melt the butter in a Dutch oven or large pot over medium heat. Add the onions, carrots, celery and garlic and cook, stirring occasionally, until the vegetables are soft, about 5 minutes. Add the tomato paste, stir to coat the vegetables, and cook for 1 minute more.
Add the broth, turkey, bay leaves and thyme, and stir to combine. Bring to a boil, then reduce the heat and simmer for 30 minutes. Stir once more and ladle the soup into bowls. Top with the parsley and serve. Leftovers can be stored in an airtight container in the refrigerator for up to 3 days.
Nutrition information per each of 6 servings:
Sodium300 mgCarbohydrates11 g
Saturated fat4 gAdded sugars0 g