In a mixing bowl, combine all-purpose flour, unsalted butter, granulated sugar, egg, egg yolk, vanilla extract, and salt. Blend the butter with the dry ingredients until it resembles coarse crumbs.

Wrap the dough tightly in plastic wrap and refrigerate it for at least 30 minutes.

In a saucepan, heat whole milk over medium heat until it’s just about to boil. Whisk together large egg yolks, granulated sugar, cornstarch, and lemon zest in a bowl. Gradually pour hot milk into the egg mixture, whisking constantly to prevent curdling.

Return the combined custard mixture to the saucepan over medium heat. Stir continuously until the custard thickens, about 5-7 minutes. Remove from heat and stir in unsalted butter and vanilla extract.

Preheat your oven to 350°F (175°C).

Roll out the chilled dough to about ¼ inch thick on a lightly floured surface. Transfer the rolled dough to the tart pan and press it into the corners.

Grease your tart pan and line it with the rolled pastry, pricking the base with a fork to avoid bubbling.

Pour the cooled custard into the prepared pastry shell and spread evenly with a spatula.

Sprinkle pine nuts or sliced almonds over the custard filling.

Bake for 30-35 minutes, or until the crust is golden brown and the custard is set yet slightly jiggly in the center.

Allow the Torta della Nonna to cool in the pan for about 30 minutes before transferring it to a wire rack to cool completely.

Dust the top with powdered sugar before serving.