Ingredients

• 14 ounces small lemons, thin-skinned
• 3 cups granulated sugar
• 2 (11-inch) Pate Brisee rounds, chilled (recipe follows)
• 6 large eggs, well beaten
• 1 large egg white, beaten
• Sanding sugar, for sprinkling

For the Pate Brisee:

• 2 1/2 cups all-purpose flour, plus more for dusting
• 1 teaspoon salt
• 1 cup (2 sticks) unsalted butter, cut into small pieces
• 1/4 to 1/2 cup ice water

Directions

For the Filling: 

1. Wash and cut 2 of the lemons into paper-thin slices. (It is very important to slice the lemons as thinly as possible; use a very sharp knife or an electric meat slicer, if one is available.) Remove the peel and pith of the remaining lemons; slice the flesh very, very thinly, and put it with the other slices in a large mixing bowl. Add the sugar and toss well to coat all the lemon slices. Cover the bowl with plastic wrap and let the mixture rest overnight, stirring occasionally. This takes the bitterness from the rind.
2. The next day, preheat the oven to 450°. Press one Pate Brisee round into a 9-inch pie plate and chill.
3. Add the beaten eggs to the sugar-coated lemon slices and mix well. Turn the mixture into the prepared pie shell, neatly arranging some of the lemon slices on top. Cut long, even slashes 1 inch apart in the other pastry round and cover the filling with it. Crimp the edges of the pie to seal. Brush the pastry top and edges with the egg white and sprinkle with sanding sugar. Bake for 20 minutes. Cover the edges of the pie with foil. Reduce the oven temperature to 375° and continue baking until the crust is golden brown and shiny, about 30 minutes. Let cool on a rack before serving.

For the Pate Brisee: 

1. Pulse flour and salt in a food processor to combine. Add butter; pulse until mixture resembles coarse crumbs with some larger pieces remaining. Evenly drizzle 1/4 cup ice water over mixture. Pulse until dough is crumbly but holds together when squeezed. If dough is too dry, add up to 1/4 cup more ice water, 1 tablespoon at a time, and pulse to combine.
2. Turn out dough onto a floured surface and divide dough in half, then shape each half into a disk. Wrap each half in plastic and refrigerate until firm, about 1 hour or up to 1 day. (Dough can be frozen up to 1 month; thaw overnight in refrigerator before using.)