*If the soup does not thicken to your liking, prepare a roux. In a separate pan, melt 1/4 cup of butter and whisk in 1/4 cup of flour. Add 1 cup of soup. Then 3 more cups. Stir until thickened. Add the mixture back into the pot of soup and incorporate. *You can transfer the soup to a slow cooker to keep warm if you will be serving the soup later.