1 1/2 teaspoons juniper berries*
1 cup heavy cream
3/4 stick (6 tablespoons) unsalted butter, melted
1 1/4 teaspoons salt
3/4 teaspoon black pepper
2 lb russet (baking) potatoes (about 4)

Special equipment: an electric coffee/spice grinder; an adjustable-blade slicer; a 2-qt flameproof shallow baking dish

Put oven rack in middle position and preheat oven to 375F.

Finely grind juniper berries in grinder.

Whisk together cream, butter, 1 1/4 teaspoons ground juniper (discard remainder), salt, and pepper in a large bowl until combined. Peel potatoes and cut into 1/8-inch-thick slices. Fold potato slices into cream mixture and transfer to baking dish, spreading evenly. Cover tightly with foil and bake until potatoes are very tender, 50 minutes to 1 hour.

Preheat broiler.

Remove foil and broil potatoes 2 to 3 inches from heat until golden, about 6 minutes.

Let stand 10 minutes before serving.

*Available in the spice section of some supermakets.