Homemade Lattice Blueberry Pie

In a large bowl, combine the flour and fine salt. Coarsely grate the frozen butter onto a piece of baking parchment. Set aside 2 tablespoons of the grated butter for later, then mix the remaining butter into the flour using a table knife until the mixture resembles coarse crumbs.

Add 3 tablespoons of ice-cold water to the flour mixture and stir until a dough begins to form. Knead very briefly just to bring it together, then divide the dough into two equal balls. Flatten each into a 2cm thick disc, wrap tightly in plastic, and chill in the refrigerator for at least 1 hour.

While the dough chills, prepare the filling by stirring together the blueberries, sugar, cornflour, ground cinnamon, lemon zest, and lemon juice in a medium bowl. Let the mixture sit for at least 1 hour to allow the sugar to dissolve and the flavors to meld.

On a lightly floured surface, roll out one pastry disc into a 26cm round. Use it to line a 22cm pie dish, allowing the pastry to slightly overhang the edges. Spoon in the blueberry mixture and scatter the reserved 2 tablespoons of grated butter over the top.