Wash and trim the vegetables, use only 4 to 5 inches of the best part of the stem. Keep the leaves for other uses.
Using a clean saucepan, bring the water to boil with the oil, salt and chicken essence. Blanch the vegetables for 1 to 2 minutes. Remove, refresh and drain. Arrange on to a platter.
Mince the ham and mash the ginger and shallot.
Heat the wok with the oil. Saute the ginger and shallot for 20 seconds then discard. Sizzle the wine, pour in the milk and seasoning to bring to the boil. Mix the cornflour and water evenly and stream into the boiling milk to thicken. Pour over the vegetables and scatter the minced ham on top. Serve hot.