For the pastry: * In a large mixing bowl sift together the flour, sugar & salt.* Add the butter & work into the flour mixture until a pea sized crumb mixture is formed.* Add the vanilla extract followed by the water one tablespoon at a time until the dough begins to come together.* Turn out onto a lightly floured surface, shape into a disc & wrap in plastic wrap. Refrigerate for 60 minutes or overnight.
For the filling: * In a large skillet over low heat add the berries, sugar, cornstarch & lemon juice. Stir to combine. * Cook until the berries begin to soften, about 5 minutes. Remove from heat. Stir in vanilla & salt. Set aside to cool slightly.
To assemble: * Preheat oven to 375(f) degrees. Line a baking sheet with parchment paper. * On a lightly floured surface, roll out prepared dough to 1/4 inch thick. Using a biscuit cutter (or mason jar lid) cut dough into 16 circles. * Transfer 8 of the circles to the prepared baking sheet. Spoon a tablespoon of the filling onto the centre of the circles. Lightly brush the edges with egg wash.* Cut a small slit in the centre of the remaining 8 circles. Place crust on top & crimp edges with a fork to seal. * Place pies in the freezer for 15 minutes to chill.* Brush the tops with remaining egg wash. Bake for 20 to 25 minutes or until golden brown. Let cool slightly before serving.