1. Mix together all the filling ingredients in a bowl. Cover with cling fi lm and chill for 2 hours. For the pastry, combine the flour, caster sugar and salt in a bowl. Rub in the butter until mostly incorporated. With a table knife, mix through the egg, then the lemon zest and juice, to form a rough dough (add a few drops of water if it’s dry). Knead briefly to bring together. Wrap ⅓ in cling film, flattening to a 1cm round. Wrap the remaining ⅔ separately and chill both for 30 minutes.
2. Strain the liquid from the filling into a pan and boil, reducing to a thick syrup. Stir in the apples; leave to cool.
3. On a floured surface, roll the large piece of pastry to a circle about 0.3cm thick. Use it to line a deep 22cm pie dish with overhang. Press into the corners, chill for 10 minutes, then tip in the filling and brush the rim with egg. Roll out the smaller piece of pastry to a 23cm circle and slice into strips of irregular thickness. Lay ½ the strips over the top, interlacing the remaining strips to create a lattice. Crimp the edges and trim any excess pastry. Brush the top with egg, sprinkle with the granulated sugar and freeze for 20 minutes. Meanwhile, preheat the oven to 220°C, gas mark 7, and put a baking tray on the bottom shelf.
4. Bake on the hot tray for 30 minutes. Reduce the oven to 180°C, gas mark 4, and cook for another 25-30 minutes (cover with foil if it browns too quickly). Cool for 30 minutes; serve with walnut honey cream.
WALNUT HONEY CREAM
Toast 75g Waitrose Walnuts; finely chopped. Whisk 300ml double cream to soft peaks, then fold in the nuts and 2 tbsp honey.