Leek Tart

FOR THE LEEKS:
Trim off the dark green parts of the leeks and the roots. Wash well to remove all grit. Cook the leeks in boiling salted water for 10 minutes then drain. Saute the leeks in 2 tablespoons of the butter over low heat for a few minutes.

FOR THE SAUCE:
In a saucepan, melt 2 tablespoons of the butter over moderate heat. Stir in 1/4 cup of the flour until well mixed. Add the milk, a little at a time, stirring constantly until the sauce is smooth. Remove from the heat. Season with a little pepper. Whisk in the Parmesan and egg yolks. Set this bechamel sauce aside.

FOR THE DOUGH:
Heap the remaining flour in a mound and make a well in the center. Add the remaining butter, a pinch of salt and a small amount of cold water. Work the mixture into a smooth, soft dough.

TO SERVE:
Roll out the dough into a circle large enough to line a 9 inch tin with 2 inch sides. Prick the pastry with a fork. Cover with a sheet of parchment (baking) paper or foil. Fill the tart shell with dried beans and bake at 350 degrees F for about 20 minutes. Remove the beans and paper. Arrange the leeks in a neat row on the pastry. Pour the bechamel over the leeks. Return the tart to the oven and bake for about 20 minutes. Let it rest for a moment or two out of the oven before turning out and serving.