10 ounces (2 cups) pine nuts
1/3 cup sugar
1 pound (3 cups) all-purpose flour
8 ounces unsalted butter, at room temperature
1 large egg
1 teaspoon pure vanilla extract
Place the pine nuts in a food processor and pulse a few times. Add the sugar and flour and continue to pulse until the nuts are finely ground. Transfer the mixture to a large bowl.
Add the butter, egg, and vanilla extract and mix to incorporate all the ingredients (the dough can be mixed by hand or in a mixer fitted with the paddle attachment). Divide the dough into three equal parts. Wrap each piece in plastic wrap and refrigerate for at least 10 minutes before using. (The extra dough can be frozen, wrapped well, for up to 1 month.
For the lemon curd4 lemons, at room temperature
1 1/2 cups sugar
1/4 pound (1 stick) unsalted butter, at room temperature
4 extra-large eggs, at room temperature
1/8 teaspoon salt
Remove the zest of the lemons with a vegetable peeler or zester, being careful to avoid the white pith. Squeeze the lemons to make 1/2 cup of juice (I added more juice as I prefer more tangy and less sweet) and set the juice aside. Put the zest in a food processor fitted with a steel blade. Add the sugar and process for 2 to 3 minutes, until the zest is very finely minced. In the bowl of an electric mixer fitted with a paddle attachment, cream the butter with the sugar and lemon zest. Add the eggs, 1 at a time, and then add the lemon juice and salt. Mix until combined.
Pour the mixture into a 2-quart saucepan and cook over low heat, stirring constantly, until thickened, about 10 minutes. The lemon curd will thicken at about 175 degrees F, or just below a simmer. Remove from the heat.
Fill the crust with warm lemon curd and allow to set at room temperature.