For the pastry, sift the flour, then place it in a processor with the cubed butter, sugar, lemon zest and cinnamon, then switch it on and process to the fine crumb stage.
Then add the eggs and process again till you have a stiff dough. Remove it from the processor, wrap in clingfilm and leave it to rest in the fridge for 30 minutes. Meanwhile, pre-heat the oven to gas mark 6, 400°F (200°C) and prepare the apples by peeling and cutting them into ½ inch (1 cm) slices, keeping them in cold water to which a tablespoon of lemon juice has been added, to prevent them browning. Then cut off two-thirds of the pastry and, on a very generously floured board, roll out the large piece to line the inside of the tin.
It will be fragile and break easily but honestly, all you need to do is simply squeeze the pastry across the base and sides of the tin, repairing any cracks as you go. Next, drain the apples, patting them dry with a clean tea towel.
Fill the pastry case with the apples, sprinkling in the sugar, cinnamon and lemon zest as you go. Then finally, roll out the reserved third of the pastry for the top and position it over the apples, sealing round the edges with your fingers and squeezing together any cracks. Brush the surface with milk, make steam holes in the centre, and bake on the centre shelf of the oven for 45-50 minutes or until a skewer inserted tells you the apples are cooked. Cool for about 20 minutes before unmoulding and serve, dusted with icing sugar. This is great with pouring cream, or for sheer indulgence, how about some mascarpone?