Heat the stock and prepare the artichokes. Prepare the artichokes, stripping off all the leaves and removing the choke. You will only be using the bottoms for this recipe.

Drop each artichoke bottom into a bowl of cold water acidulated with two thirds of the lemon juice as soon as you have prepared it to prevent discoloration. Drain and slice. Place these slices in a wide non-stick frying pan, add 5 fl oz (150 ml) of the stock, cover with a lid or foil and poach for 10 minutes.

Melt the butter in a large, heavy-bottomed saucepan; stir in the flour and cook over a low heat, stirring continuously, for 1-2 minutes. It should not colour. Draw aside from the heat and keep beating vigorously with a balloon whisk or hand-held electric beater as you gradually pour in the hot stock, adding a little at a time.

Return to a gentle heat, add the artichoke slices and their cooking juices, cover and simmer for 30 minutes.

When the artichokes are very tender, beat with a hand-held electric beater or put through a vegetable mill. Stir the milk into this puree and reheat to boiling point. Season the soup with salt and pepper.

Beat the egg yolks and cream together briefly in a small bowl with a pinch of salt and a little freshly ground white pepper.

Gradually beat in 2 tbsp of the hot soup. Take the saucepan containing the boiling hot soup off the heat; pour the slightly thinned egg and cream liaison into the soup in a very thin stream, beating continuously.

Return the saucepan to a very low heat and keep stirring as the soup thickens slightly. It must not boil. Remove from the heat and stir in some of the remaining lemon juice.