For the dough, put flour, almonds, 150 g sugar, salt, eggs, 2 tablespoons cold water and butter in flakes in a mixing bowl. Knead first with the dough hooks of the hand mixer, then with your hands quickly to a smooth dough. Put approx. 2/3 of the dough into a greased and flour-sprinkled tart mould with lift-off base (approx. 26 cm Ø) and press it down to a base with a rim. Chill for about 30 minutes.
Roll out the remaining dough on a floured work surface in a rectangular shape (approx. 20 x 30 cm). Cut into approx. 10 strips (approx. 2 x 30 cm). Weave strips on a floured round plate (approx. 30 cm Ø) to form a grid. Keep cold.
Wash and clean strawberries and rhubarb. Halve the strawberries. Cut the rhubarb into small pieces. Boil up the apple juice to 4 tbsp. Mix pudding powder, 50 g sugar and 4 tbsp. juice. Stir into the boiling juice, bring to the boil and simmer for about 1 minute. Stir in fruits. Spread on the dough base in the mould.
Slide the dough grid from the cake plate onto the cake. Cut off any excess dough and press the grid around the edge of the cake. Mix egg yolk and 2 tbsp. water. Spread a thin layer of the dough onto the strips. Sprinkle with sugar crystals. Bake in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: see manufacturer) for approx. 1 hour. Cover with aluminium foil after about 45 minutes. Remove from the oven and let cool on a cake rack. Remove the tart from the tin and dust with icing sugar. Serve with vanilla ice cream.