Make the dough: In a large bowl, combine the flour, salt, and sugar (if using). Add the cold butter and cut it into the flour mixture using a pastry cutter, fork, or your hands until it resembles coarse crumbs. Gradually add the ice water, a tablespoon at a time, mixing until the dough comes together.
Chill the dough: Divide the dough in half, shape into discs, and wrap in plastic wrap. Refrigerate for at least 30 minutes before rolling out.
Roll out the dough: On a lightly floured surface, roll out one disc of dough into a circle large enough to fit your pie dish. Gently place the rolled dough into the dish, trimming any excess edges.
Add the filling: Once your filling is prepared, pour it into the pie crust.
Top with the second crust: Roll out the second disc of dough and place it on top of the filled pie. Trim the excess dough and pinch the edges to seal. Cut small slits in the top crust to allow steam to escape.
Bake: Preheat the oven to 375°F (190°C). Bake the pie for 45-60 minutes, or until the crust is golden brown and the filling is bubbly. Let cool before slicing.
Prepare the filling: Mix the fruit, sugar, cornstarch, cinnamon (if using), lemon juice, vanilla extract, and salt in a large bowl. Stir gently to combine, making sure the fruit is evenly coated.
Fill the crust: Pour the fruit mixture into the prepared pie crust.
Dot with butter: For extra richness, dot the filling with small pieces of butter before covering with the top crust.
Prepare the custard: In a medium saucepan, heat the cream (or milk) with sugar, cinnamon, and salt over medium heat. Whisk the eggs and cornstarch together in a separate bowl.
Temper the eggs: Slowly pour some of the hot cream mixture into the eggs, whisking constantly to avoid curdling. Gradually pour the egg mixture back into the saucepan, stirring until the mixture thickens.
Cool and pour: Remove from heat and add the vanilla extract. Allow the custard to cool slightly before pouring it into the pie crust.
