Bring milk to just a boil and then set aside to cool. Just cool enough not to bite the finger to touch (about 120 degrees).
Pour warm milk in a glass or Pyrex bowl and add the Mahdzoon starter. Mix well bu stirring the starter in, and cover. Completely cover the bowl with towels top and bottom to maintain an even temperature. Keep covered at room temperature until Mahdzoon has set [3-4] hours.
Refrigerate for 8 hours before serving. To store, keep in refrigerator. Mahdzoon will keep well, a week or more
The owner of this pot de creme cup describes it as being from the Napoleon III era from the Sevres factory in France