1. Fill a deep saucepan wide enough to take the whole cauliflower half full of water; add salt and bring to the boil.
2. Prepare the cauliflower, trimming off the leaves and the hard remains of the stalk, and cut a deep cross in the base. Rinse the cauliflower thoroughly and place in the boiling water which should completely cover it. (Add a pinch of bicarbonate of soda or a cube of white bread to help prevent a strong smell as it cooks, if wished.) Cover and boil gently for 17-20 minutes or until tender but still firm.
3. Meanwhile, make the sauce: chop the parsely, the ham and the hard-boiled eggs, keeping them separate. Squeeze the juice out of the lemon and strain. Set aside.
4. Melt the butter in a small saucepan, add the breadcrumbs and fry for 1-2 minutes until lightly browned. Stir in the lemon juice and the cream, and remove from the heat. Use two large slotted spoons or a spoon and a slotted ladle to take the whole cauliflower out of the water in the pan; drain as you hold it over the pan and place carefully in a heated serving dish.
5. Make sure the sauce is hot but not boiling, stir in the ham, eggs and parsley, a pinch of salt and plenty of freshly ground pepper. Pour this all over the cauliflower and serve at once on heated plates.