For the apple and Riesling cake, put the flour, almond kernels, a little salt, chopped butter and the egg in a large enough bowl. Knead together first with the dough hook of the mixer, then with your hands to form a smooth dough.
Wrap in plastic wrap and refrigerate for half an hour.
In the meantime, mix the custard powder and 10 tablespoons of wine. Bring remaining wine, sugar and 2 pkg. vanilla sugar to a boil. Stir in prepared pudding powder, bring to a boil while stirring, and remove from heat.
Remove peel from apples, cut into quarters and core. Cut the quarters diagonally into 1/2 cm thick slices, immediately mix with the juice of one lemon and fold into the wine pudding.
Grease a cake springform pan (26 cm ø) and dust with flour. Roll out the shortcrust pastry on the floured surface into a round (34 cm ø) and bake in the mold, forming a rim and pressing it smooth.
Pour the apple-wine pudding on top. Bake the cake on the 2nd rack from the bottom in the preheated oven at 180 °C for 75 minutes. Cover loosely with baking paper after 45 minutes. Leave the cake to cool completely in the refrigerator overnight.
Whip the cream with 1 sachet of vanilla sugar until stiff. Remove the cake from the pan, spread the whipped cream on the surface and dust with cinnamon.
Preparation Tip:
Important: Allow the apple Riesling cake to cool before cutting.