Method:

1. Clean leek pieces and bake on both sides for one minute in a skillet, adding pepper and salt and nutmeg.
2. Add the chicken stock and allow to simmer until leeks are done.
3. Drain leeks, keep warm and keep the stock aside.
4. Melt butter on low heat, add the flour and stir until mass is coherent and slightly dry.
5. Add milk and leek stock for a total of 1 liter to the butter and flour mix and heat on medium heat while continuously stirring until the right thickness. In case the sauce is too thick, add some milk, in case the sauce is too thin, keep stirring and allow to simmer until the right thickness is achieved.
6. Add seasoning and lemon juice and taste. Add salt and pepper to taste
7. Filter sauce through a fine sift
8. Pour sauce over leeks and serve