Knead the flour, hazelnuts, 50 g sugar, salt, egg and butter in small pieces first with the dough hooks of the hand mixer, then with your hands to a smooth dough. Grease a rectangular tart mould with lift-off base (21 x 29 cm). Roll out the short pastry rectangularly (approx. 24 x 32 cm) on a floured work surface. Line the tart mould with the pastry, press on, cut off any protruding edges. Chill for about 1 hour.
Place a piece of baking paper on the dough. Spread dry peas on top. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for about 20 minutes. Take the tart out of the oven, remove the baking paper with the dried peas and let it cool down
Roast the almonds in a pan without fat until golden brown. Soak the gelatine. Sort raspberries. Select blueberries, wash and drain well. Wash, stalk and stone the cherries. Stir 75 g sugar, groats powder and 6-7 tbsp. juice until smooth. Bring the rest of the juice and 250 ml water to the boil in a pot, stir in the mixed groats powder, bring to the boil while stirring and simmer for about 1 minute while stirring. Remove from the stove, let it cool down for about 5 minutes. Squeeze the gelatine, add and stir until the gelatine has dissolved
Fold in cherries, raspberries and blueberries. Spread the red fruit jelly on the tart and chill for about 2 hours. Remove the tarte from the tin, sprinkle the edge with almonds and serve on a plate. Whipped cream tastes good with it
waiting time approx. 3 1/2 hours