First knead the flour, icing sugar, 1 egg and butter in pieces with the dough hooks of the hand mixer, then quickly knead with your hands to a smooth dough. Cover and chill for about 30 minutes. In the meantime wash apples, dab dry, cut in half, core and cut halves into thicker slices. Put the apple slices in water with some lemon juice. Mix crème fraîche, milk, 3 eggs, vanillin sugar and sugar.
Grease a springform pan (26 cm Ø) and dust with flour. Roll out the dough on a floured work surface until round (approx. 32 cm Ø). Line the form with the dough and press the rim well down. Sprinkle the dough base with hazelnuts. Drain the apple slices and layer them in the mould. Pour the egg mixture over the top, leaving 3-5 mm space to the upper rim. Bake in the preheated oven (electric range: 175 °C/ convection oven: 150 °C/ gas: level 2) for 40-55 minutes until golden brown. Put jam and 1 tablespoon of water in a pot, bring to the boil and pass through a fine sieve. Take out the cake, let it cool down briefly and spread with the jam.
Drain the apple slices and layer them in the mould. Pour the egg mixture over the top, leaving 3-5 mm space to the upper rim. Bake in the preheated oven (electric range: 175 °C/ convection oven: 150 °C/ gas: level 2) for 40-55 minutes until golden brown. Put jam and 1 tablespoon of water in a pot, bring to the boil and pass through a fine sieve. Take out the cake, let it cool down briefly and spread with the jam. Put the cake on a plate and dust with icing sugar
10 minutes waiting time