Make -Ahead Swiss Potato Gratin - cooking recipe

Ingredients

3 lbs yukon gold potatoes, peeled, thinly sliced (8 cups)
2 tablespoons butter or 2 tablespoons margarine
2 leeks, white and light green parts only, sliced
3 cups half-and-half cream
1/2 cup all-purpose flour
1/3 cup grated parmesan cheese
1 teaspoon salt
1/8 teaspoon cayenne pepper
1/8 teaspoon ground nutmeg
1 cup shredded swiss cheese

Preparation

Line 2 baking sheets with paper towels. In a pot combine potatoes with enough water to cover. Bring to a boil; Drain.
Arrange on baking sheets.
In a skillet over medium-high heat melt butter and add leeks.Cook until softened, 3 minutes.
Whisk together next 6 ingredients in shallow 2 1/2 quart baking dish layer half of potatoes, half of leeks and 1/2 cup swiss cheese.
Pour 1 1/2 cups half and half cream mixture over cheese.
Repeat layering, reserving remaining Swiss cheese.
Cover and refrigerate.
Remove from refrigerator 1 1/2 hrs before baking.
Preheat oven to 375 degrees.
Bake covered until bubbly, 1 hour,15 minutes.
Preheat Broiler.
Uncover casserole; sprinkle with remaining swiss cheese.
Broil until just browned, 3 minutes.
MAKE IT IMMEDIATELY! AND SKIP REFRIDERATING THE CASSEROLE AND REDUCE BAKING TIME BY 30 MINUTES.