Start to finish: 4 hours (30 minutes active)
For the dough:
1 1/2 cups all-purpose flour
1/2 cup cake flour
1 teaspoon salt
1 1/2 sticks chilled, unsalted butter, diced, plus additional for coating the pan
4 tablespoons chilled vegetable shortening
1/2 cup ice water, plus more as needed
For the filling:
6 strips crisply cooked bacon
3 large eggs
1 cup heavy cream
Salt and ground black pepper, to taste
Nutmeg, to taste
In a food processor, combine the all-purpose flour, cake flour, salt and butter. Pulse 5 to 6 times in 1/2-second bursts to break up the butter. Add the shortening, then immediately add the ice water while pulsing 2 or 3 times.
The dough should resemble a mass of small lumps that hold together when pressed. If the dough is too dry, pulse in additional water, a few droplets at a time. When the dough is ready, transfer it to the counter.
With the heel of your hand, rapidly and roughly push egg-size blobs out in front of you in 6-inch smears. Gather the dough in a relatively smooth cake, wrap in plastic and refrigerate for at least 2 hours and up to 2 days. It also can be frozen for several months.
When ready to bake, use butter to coat a 9-inch tart pan with removable bottom.
Cut the chilled dough in half and reserve one piece, refrigerated, for another use. On a lightly floured counter, rapidly roll the remaining piece of dough into a circular shape about 1/8 inch thick and 1 1/2 inches larger than the tart pan.
Roll the dough onto the rolling pin and unroll onto the pan. Lightly press the dough into place. To make sturdy sides, fold the excess dough into the pan against the sides, smoothing the top edge as you go.
Prick the bottom of the dough all over with a fork. Cover with plastic wrap, then chill for at least 30 minutes before baking.
Meanwhile, heat the oven to 450 F. When the tart shell has chilled, use butter to coat the shiny side of a sheet of foil several inches larger than the tart shell. Lightly press the foil, buttered side down, into the chilled tart shell along the sides and bottom.
To prevent the bottom from rising and the sides from falling, fill the shell with beans, rice or pie weights.
Bake for 10 to 15 minutes, or until the bottom of the tart shell is set but still soft. Remove the foil and beans, prick the bottom again with a fork, then bake for another 2 minutes.
Remove the tart shell from the oven and set aside. Reduce the oven temperature to 375 F.
Break the bacon into pieces and scatter them in the tart shell.
In a small bowl, whisk the eggs, cream, salt, pepper and nutmeg. Pour the mixture into the tart shell, filling to within 1/8 inch of the rim. Bake for 30 to 35 minutes, or until puffed and browned. Unmold onto a platter and serve warm or room temperature.
(Recipe adapted from Julia Child’s “Julia’s Kitchen Wisdom,” Knopf, 2009)