(Potatoes in their jackets with leek sauce).

2 lbs. potatoes
2-4 leeks (raw)
1 c. cream and-or 1/2 c. milk
Salt, pepper, some vinegar and mustard

Leeks must be chopped, add cream (and milk). Wait for an hour before adding salt, pepper, vinegar and mustard. Eat potatoes with this sauce.

Translation from Luxemburger Cookbook including conversion from the metric by Dr. Marianne Ney).