Potato Soup - cooking recipe

Ingredients

4 Tbsp. butter
4 Idaho potatoes, peeled and thinly sliced
4 large leeks, washed and shredded
1 1/2 c. water
1/2 tsp. Dijon mustard
1 1/2 c. milk
2 egg yolks
1/2 c. heavy cream
2 Tbsp. chopped parsley
1/2 c. fried croutons
freshly cracked black pepper

Preparation

Melt the butter in a deep heavy pan.
Add the sliced potatoes and 3/4 or all of the leeks with 1/2 cup water, mustard, salt and pepper.
Cover and cook over low heat until the vegetables are soft and mushy.
Pour in the milk and 1 cup of water.
Stir over low heat until the soup comes to a boil.
Remove from the heat and let stand 15 minutes, then puree in an electric blender.
Beat the egg yolks with the heavy cream in a separate bowl.
Stir the yolk mixture into the soup over low heat; do not boil.