Combine the all-purpose flour and fine salt in a medium bowl. Cut in the unsalted butter with a pastry cutter or fingertips until the mixture resembles coarse crumbs with pea-size bits.
Add the large egg yolk and drizzle in the ice water, tossing just until the dough holds together when pressed; you may not need all the water. Gather into a disc, wrap, and chill 30 minutes.
Roll the dough between two sheets of parchment into a 12-inch round. Peel off the top sheet, invert into a 9-inch tart pan with removable bottom, and press into the edges. Trim excess, dock the base with a fork, and chill 15 minutes while you heat the oven to 375°F (190°C).
Line the crust with the reserved parchment and fill with pie weights. Bake 20 minutes, then remove weights and parchment and bake 5–8 minutes more until the shell looks dry and lightly golden. Set aside to cool slightly.
Cut the thick-cut bacon into 0.5-inch pieces. Cook in a skillet over medium heat until lightly browned and some fat has rendered, 6–8 minutes. Drain on paper towels and let cool slightly.
Whisk the large eggs, heavy cream, and whole milk in a bowl until smooth. Season with the freshly ground black pepper and freshly grated nutmeg.
Scatter the bacon evenly in the warm crust. Reduce oven temperature to 350°F (175°C). Pour in the custard.
Bake 25–30 minutes until the custard is just set with a slight wobble in the center and the top is lightly golden. Cool 10–15 minutes, unmold, slice, and serve warm or at room temperature.