Blueberry lattice pie

Divide the pastry into 200g and 300g pieces. Wrap the smaller piece and chill for later. On a lightly floured surface, roll the larger piece to the thickness of a £1 coin and use to line a 23cm fluted tart tin, 2-4cm deep. Trim the edges so there’s about 1-2cm pastry overhanging; chill for 30 minutes.

Preheat the oven to 200oC, gas mark 6. Prick the base of the pastry all over with a fork, then line with baking parchment and fill with baking beans. Blind bake for 10 minutes, then remove the parchment and beans. Brush all over with egg white (reserve the remainder) and bake for 10 minutes more. Cool fully; trim the overhanging pastry with a serrated knife.

Mix the cornflour, 4 tbsp sugar, the lemon zest, 1⁄2 tsp cinnamon and a pinch of salt in a large mixing bowl. In another bowl, use a fork to very lightly crush 100g blueberries with the lemon juice, then toss with the remaining berries into the cornflour mixture, ensuring everything is evenly mixed. Tip this mixture into the cooled tart case.

Roll the reserved chilled pastry into a rectangle at least 28cm long and about 20cm wide. Cut 10 long, equal strips and arrange these over the blueberries in a lattice formation. Trim the edges level with the tin. Chill for 30 minutes.

Lightly whisk the reserved egg white until frothy and brush over the top of the lattice. Mix the remaining 1⁄2 tbsp sugar and 1⁄4 tsp cinnamon and sprinkle over the lattice pastry. Bake for 35-45 minutes, until golden and bubbling. Cool completely before serving with crème fraîche, if liked.