Roll out the shortcrust pastry on a lightly floured work surface (approx. 30 cm diameter). Place in a springform pan (24 cm diameter) lined with baking paper. Press the edge about 6 cm high.
Peel the apples, remove the core with an apple cutter. Place the whole fruits on the dough base. Whisk together milk and cream, sugar and custard powder and, while stirring constantly, heat and cook in a saucepan until the liquid thickens and bubbles. Stir in the egg yolks and immediately pour over the apples. Sprinkle the cake with flaked almonds.
Bake in a preheated oven at 180 ° C for about 45 minutes.
If necessary, cover the last 15 minutes with aluminum foil so that it does not burn.