Peel, quarter and core the apples. Cut into large pieces and sprinkle with lemon juice. Mix 100 g flour, 60 g sugar, 1 packet of vanilla sugar, 1 pinch of salt, nuts, egg yolk and 75 g fat in pieces with the dough hooks of the hand mixer to form crumbles.
Set aside. Cream 200 g soft fat, 200 g sugar, 1 packet of vanillin sugar and 1 pinch of salt. Stir in the eggs bit by bit. Mix 300 g flour and baking powder, alternating with the cream.
Grease a springform pan (35 x 24 cm) and dust with flour. Put the dough into the form and smooth it down. Drain the apple pieces and spread them on the dough, sprinkle crumbles over them. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 45 minutes.
Loosen the rim of the springform pan and let the cake cool down in the pan. Serve dusted with icing sugar. Whipped cream tastes good with it.