Combine the flour and salt in a food processor and briefly pulse 2-3 times. Add the butter and pulse until mostly pea-size pieces of butter remain (a few larger pieces are okay). Slowly pour ¼ cup of the water into the food processor while pulsing the mixture until it begins to form a ball (no more than 30 seconds). Add the additional tablespoons of water, one at a time, if your mixture is too dry to form a ball.

Remove the dough from the food processor, form it gently into a disc, and wrap tightly in plastic wrap. Refrigerate for at least 1 hour or overnight.

Preheat the oven to 375°F and place rack in the bottom third of the oven. Unwrap the round of dough and place on a lightly floured surface. Flour a rolling pin and your hands. Roll the dough out into a 12-13-inch circle (about ⅛ inch thick). Occasionally lift the dough from the surface to ensure it is not sticking and add more flour to the working surface and top of the dough as needed.

Transfer the rolled dough to a 9-inch pie pan and gently press dough into the bottom and sides of the pie pan. Tuck excess dough under, along the rim of the pie pan, and use your fingers and thumb to crimp the edge. Chill the unbaked pie shell in the freezer for at least 15-20 minutes (and up to an hour) while the oven preheats and you make the filling.

While the pie dough is chilling, make the filling. In a large bowl or stand mixer, whisk together the eggs, heavy cream, whole milk, salt, and a few grates of fresh nutmeg until smooth. Set aside.

Sprinkle the cooked bacon into the bottom of prepared and chilled dough. Pour egg mixture on top of bacon, then sprinkle the cheese on top. Bake on the bottom rack, rotating halfway through, until crust is golden brown on edges and bottom and the egg mixture is set, about 35-45 minutes. If the crust still needs more time, cook in additional 5-minute increments. Let cool slightly, sprinkle with finely chopped chives, and serve warm or at room temperature.