In a large soup pot, melt the butter over medium heat.
Add the onion, carrots, and celery and cook until softened, about 5-7 minutes.
Add the garlic, Italian seasoning, salt, and pepper, and stir well to combine.
Add in the broth and turkey. Bring to a simmer and let it cook for 10 minutes.
In a bowl or a mason jar, combine the flour and milk. Whisk or shake to combine.
Add to the soup pot and cook for 5 minutes, until it is slightly thickened.
Add the gnocchi and cook another 5 minutes, until the gnocchi is soft and the soup has thickened more.
Add the Parmesan cheese and stir well to combine.
Serve and enjoy!