Recipe: Creamy Potato Gratin

My mother-in-law was in town this weekend, to make dinner for Mrs. Brave Astronaut and for OSG and his new family. We had the great summer meal, flank steak, a tomato, mozzarella, and basil salad, and an outstanding scalloped potatoes. This recipe will most definitely appear again, but it is not on the heart-healthy menu. But, oh well.

Creamy Potato Gratin Drizzled with Truffle Oil
(serves 8 - I won't mention that the five of us ate the whole dish)

• 1/2 tbsp. butter for greasing baking dish
• 8 oz. Italian Fontina cheese, well chilled
• 3 lbs. Yukon Gold potatoes, peeled and cut into 1/8 inch thick slices
• kosher salt and freshly ground black pepper
• 1 1/2 cups creme fraiche (see note)
• 1 tbsp. truffle oil, optional (see note)
• 1 tbsp. chopped rosemary

Butter a 9x13 inch oven to table baking dish.

Remove rind and grate cheese using a hand grater. (Since Fontina cheese is a soft cheese, it is easier to grate with a hand grater than in a food processor.)

Place half the potatoes, overlapping slightly, in prepared dish. Salt and pepper slices generously. With a rubber spatula, spread half the creme fraiche over the potatoes. Then sprinkle half the cheese over the creme fraiche. Make a second layer in the same way using the remaining potatoes, creme fraiche and cheese.

Bake gratin on center rack of a preheated 400-degree oven, uncovered, 30 minutes. Then, lower heat to 350 degrees and bake until potatoes are tender when pierced with a knife and a golden brown crust has formed on top, about 30 minutes more. Check occasionally, and cover with a sheet of foil if potatoes become too brown.

Remove gratin from oven and let stand 10 minutes. (Gratin can be prepared 4 hours ahead; cool, cover loosely with foil and leave at room temperature. Reheat, uncovered, in a preheated 350-degree oven until hot, about 15 minutes.) Drizzle potato gratin with truffle oil and sprinkle with rosemary.

Note: Creme fraiche is available in many groceries, but if you can't find it, you can make your own by whisking together 1 1/4 cups heavy whipping cream and 1/2 cup sour cream in a medium non-reactive bowl. Let stand at room temperature until thickened, 6 hours or overnight. Cover and refrigerate. (Creme fraiche can be stored up to 1 week, covered, in refrigerator.) Makes about 1 3/4 cups. Truffle oil is available in specialty food stores and some markets.