Leek And Potato Gratin
|White and pale green parts of leek||2 1⁄4 Pound, well washed and chopped (About 3 Large Ones)|
|Unsalted butter||3 Tablespoon|
|All purpose flour||2 Tablespoon|
|Half-and-half||2 Cup (32 tbs), scalded|
|Grated parmesan cheese||6 Tablespoon (1/4 Cup Plus 2 Tablespoons)|
|Grated gruyere cheese||6 Tablespoon (1/4 Cup Plus 2 Tablespoons)|
|Dijon mustard||2 Teaspoon|
|Freshly grated nutmeg||To Taste|
|Russet baking potatoes||1 1⁄2 Pound, peeled and cut into 1-inch cubes (About 3 Medium Pieces)|
In a saucepan cook the leeks in 2 tablespoons of the butter over moderate heat, stirring, until they are soft ened.
Add the flour and cook the mixture over low heat, stirring, for 3 minutes.
Add the half-and-half, bring the liquid to a boil, and simmer the mixture, stirring occasionally, for 5 minutes.
Stir in 1/4 cup each of the Parmesan and Gruyere, the mustard, the nutmeg, and salt and pepper to taste.
Meanwhile, in a saucepan combine the potatoes with enough water to cover them by 2 inches, bring the water to a boil, and simmer the potatoes for 1 minute.
Drain the potatoes.
Transfer the potatoes to a buttered 1 1/2 quart baking dish.
Spoon the leek mixture over the potatoes, sprinkle it with the remaining cheeses, and dot the top with the remaining butter.
Bake the gratin in a preheated 400° F. oven for 35 to 40 minutes, or until the potatoes are tender and the top is golden brown.