Make a roux from by melting the butter and then cooking the flour.
Gradually add milk to make a cream sauce.
Add in 3 cups of chicken broth, green beans, mashed potatoes, and turkey.
Boil water in a separate pan and cook tortellini al dente.
Once everything in the soup mixture is warm and well incorporated season to taste.
Add in tortellini.
If you want it thinner add some more broth.