Use a large saucepan to melt the butter. Add the shallots, celery, and chicken. Lower to a low flame and keep cooking while stirring for 8 minutes.

Pare the lemons thinly and blanch the lemon rinds for 3 minutes in boiling water. Squeeze all the liquid out of the lemons.

Pour in the lemon juice, rind and chicken stock into the saucepan and slowly bring the soup to a boil. Let it simmer for 55 minutes.

Add in the salt, pepper and heavy cream. Heat it through but make sure it does not boil.

Serve the soup hot.