Bring 10 cups of water to a boil in a large pan. Peel the onion and leave it in boiling water. Add the lamb shanks, bring to a boil, cook at low heat for about an hour. Take the shanks out, remove the meat from the bones and divide into small pieces. Pass the broth through a strainer. Bring the volume of the broth to ten cups by adding boiling water.

Melt 6 tablespoons of butter in a non-stick pan. Add the flour,mix well with the butter turning continuously over medium heat for about three minutes. Add 1/2 cup of broth, keep stirring continuosly until the broth is completely absorbed and the mixture reaches a smooth consistency. Repeat the process by adding 1/2 cup broth at a time until you consume it all. Add the meat and simmer for 10 minutes.

When you are ready to serve, melt 1 tablespoon butter in a small pan, add paprika to the melt, then pour it on the soup.