How to Make It
Stir together flour, butter, and 3/4 teaspoon salt in a large bowl. Using your fingertips, rub butter into flour mixture until mixture resembles coarse meal. Make a well in center. Stir together 1 egg yolk with enough ice water to equal 1/4 cup; pour into well, and stir into flour mixture until just moistened. Turn dough out onto a lightly floured surface. Knead dough just until it comes together. Divide dough into 2 disks. Wrap each disk in plastic wrap, and chill at least 8 hours or overnight.
Preheat oven to 400°F. Unwrap 1 dough disk, and roll into a 13-inch round on a lightly floured surface; fit into a 9-inch pie pan. Chill 10 minutes.
Meanwhile, soak potato slices in ice water to cover (to remove surface starch) about 5 minutes; drain and pat slices dry. Toss potatoes with parsley, pepper, and remaining 1/4 teaspoon salt. Place bacon in a large skillet, and cook over medium-high, stirring occasionally, until wilted and just browned on edges, about 2 minutes. Drain bacon on paper towels.
Arrange half of potato slices in refrigerated pie shell, overlapping slices. Sprinkle evenly with bacon; top with remaining potato slices, overlapping slices. Spread crème fraîche over potatoes, and arrange egg slices on top. Unwrap remaining dough disk, and roll into a 10-inch round on a lightly floured surface. Place round on top of pie. Trim edges and fold dough under. Crimp edge as desired. Using the tip of a knife, prick top of pie twice.
Stir together 1 teaspoon water and remaining egg yolk; brush over top of pie. Bake pie in preheated oven on middle rack 20 minutes; reduce oven temperature to 350°F, and bake 50 minutes. Reduce oven temperature to 300°F, and bake until top is golden brown, about 10 minutes.
Let pie rest 10 minutes before serving.