Melt the onion in a little butter until it is soft and transparent, then add the artichokes. Turn them in the onion and butter for a few minutes, then add the stock and seasoning. Bring slowly to the boil and allow to simmer for 30 minutes.
Liquidize or sieve and return the soup to the pan. Reheat it, adding a little more stock or milk if necessary to achieve the right consistency. Just