Pastry 300g (10½ ounces) plain flour Pinch of salt ¼ tsp ground cinnamon 150g (5 ounces) unsalted butter, chilled and cubed 2 Tbsp caster (superfine granulated) sugar 100ml (about 3½ fluid ounces) ice cold water Demerara sugar for sprinkling Fruit filling 500g (about 1 pound) dark-fleshed plums 125g (about 4½ ounces) blueberries 50g (about ¼ cup) caster (superfine granulated) sugar Finely grated zest 1 lemon ¼ tsp ground cinnamon 2 Tbsp cornflour (USA cornstarch)
1 Put flour, salt, cinnamon and butter in the bowl of a food processor. Process briefly until butter is just mixed in. Whiz in sugar. Add water and pulse until dough forms a ball. Read about making pastry here.
2 Turn dough on to a floured board and knead gently into a ball. Wrap in plastic wrap and chill until firm.
3 Roll out pastry to a 30cm (12”) round on a lightly floured surface. Transfer to a baking sheet lined with baking (parchment) paper.
4 Halve plums, remove stones and cut into wedges. Mix plums and blueberries, sugar, lemon zest, cinnamon and flour in a bowl and pile into the centre of the dough. Fold in pastry edges and pinch together.
5 Sprinkle edges of pastry with demerara sugar. Bake pie for 35-40 minutes in an oven preheated to 180°C (350°F), or until the pastry is golden and the fruit tender. Serve warm or at room temperature.