1 lb. frozen all-butter puff pastry, thawed but cold
1 lb. med. waxy potatoes
2 garlic cloves, finely chopped
2 tbsp. finely chopped parsley
3/4 tsp. salt
1/2 tsp. freshly ground pepper
2 egg yolks
1 tbsp. milk
1/2 c. heavy cream

Preheat the oven to 400 degrees. On a lightly floured surface, roll out 2/3 of the puff pastry to a 13-inch circle, about 1/8-inch thick. Transfer the dough to a 10-inch fluted ceramic pie dish.

Peel the potatoes and slice them as thin as possible. Place in a medium bowl. Chop the garlic with the parsley until very fine and sprinkle over the potatoes. Add the salt and pepper and toss gently to mix. Layer the potatoes in the dough-lined dish.

Roll the remaining dough into a 12-inch circle and place on top of the potatoes. Pinch the edges of the bottom and top crusts together to seal, then carefully roll the rim over itself onto the top crust.

In a small bowl, beat 1 of the egg yolks with the milk until blended. Brush the top of the pie and the rim with the egg wash. Cut four 1/2-inch-wide holes in the top crust to let steam escape during baking. Bake the tourte for 40 minutes, or until the top is golden and the potatoes feel tender when pierced.

Remove the tourte from the oven. In a small bowl, beat the remaining egg yolk with the cream and pour the mixture into the tourte through a funnel inserted in the holes in the top crust. Bake the tourte for 20 minutes longer. Serve hot, warm, or at room temperature. Yield 6-8 servings.