Melt the butter in a large pot over medium heat. Add the onion, celery, and carrots and sauté until soft.
Mix in the garlic, sun-dried tomatoes, and seasoning and cook for an additional minute.
Stir in 4 cups of chicken broth, chicken, and gnocchi. Bring soup to a boil, reduce heat, and simmer until chicken is heated through and gnocchi starts to float.
Stir in the heavy cream and spinach and simmer until spinach starts to wilt. Add any additional seasonings needed and serve.