Method

• 1.
  For hazelnut pastry, combine hazelnut meal, flour, caster sugar and 1/2 tsp fine sea salt in a bowl. Add butter and toss to coat. Turn out onto a clean work surface, then, using a pastry cutter, cut butter into flour until it resembles very coarse crumbs.
• 2.
  Combine vinegar, 100ml chilled water and 4 ice cubes in a jug. Make a well in centre of flour mixture, add vinegar water (add a little extra water if needed) and combine to form a rough dough. Halve pastry and enclose in plastic wrap. Chill for at least 2 hours or up to 2 days.
• 3.
  Meanwhile, to make the filling, place cherries, sugar, star anise, zest, vanilla pod and seeds, and 1 cup (250ml) water in a saucepan over medium-low heat. Cook, stirring occasionally, for 10 minutes until cherries are softened. Remove 1/2 cup (125ml) liquid and combine in a bowl with cornflour. Return cornflour mixture to cherry mixture and cook, stirring occasionally, for 4 minutes or until thick. Cool completely, then stir through apple.
• 4.
  Roll out 1 portion of pastry on a lightly floured work surface to 3mm thick and use to line a 20cm x 15cm x 4cm baking dish. Chill for 30 minutes. Roll out remaining pastry to 3mm thick and cut into twenty 1cm-wide strips. Place on a baking tray lined with baking paper and chill for 30 minutes.
• 5.
  Preheat oven to 200°C. Scatter base of pastry case with milk powder, then pour in cherry filling. Brush pastry edges with eggwash, then make a lattice pie topping with pastry strips. Fold pastry edges over lattice strips to seal. Brush with eggwash, then scatter with demerara sugar. Place pie on a baking tray and bake for 20 minutes or until pastry starts to colour. Reduce oven to 180°C and bake for a further 30 minutes or until pie is dark golden and bubbling.
• 6.
  Rest for 30 minutes, then serve with ice cream.