To make the base beat the butter and sugar together in an electric mixer fitted with a paddle attachment until light and fluffy. Add the vanilla and iced water and then beat in the egg yolks one at a time, beating well between each addition. Finally sift in the flour and stir through until just combined.
Press ⅔ of the base into a 26cm springform tin covering the base and the sides. Roll out remaining pastry between 2 sheets of greaseproof paper and refrigerate both while you make the filling.
To make the filling combine the apples, sugar, water, cinnamon and nutmeg in a large saucepan and place over a low heat and cook for 15 minutes, stirring frequently. Strain the apple mixture and set aside to cool completely.
Preheat the oven to 180 Celsius (355 Fahrenheit) and remove the pastry from the refrigerator and sprinkle the ground almonds over the base which will help prevent the base from becoming too soggy. Pour the drained and cooled apples over the top and then top with the pastry lid. Press the edges of the pastry together to seal and then brush with the egg yolk glaze and sprinkle with extra sugar.
Bake for 45 to 50 minutes, or until golden. Serve warm with freshly whipped cream.
Notes
I used a mixture of Grannysmith and Sundowner apples.