Cut the butter into pieces. Knead flour, ground almonds, 75 g icing sugar, butter and egg first with the dough hooks of the hand mixer, then with your hands to a smooth dough. Wrap the dough in foil and chill for about 30 minutes
Wash, clean and slice the rhubarb. Bring the juice and vanillin sugar to the boil. Stir 5 tablespoons of water and starch until smooth and stir into the boiling juice. Simmer for about 1 minute while stirring, then add the rhubarb. Simmer again for another 1 minute, then put aside. Let cool lukewarm while stirring occasionally
Roll out the dough 2-3 mm thin on a floured work surface. Cut out 6 circles (approx. 14 cm Ø) and line the greased tartlets (approx. 12 cm Ø) with them. Cut off any protruding edges. Knead the dough again and roll out again and cut out circles
Prick the bottom several times with a fork. Place a piece of baking paper on each pastry and pour in dried peas. Bake in the preheated oven on the lower shelf (electric oven: 200 °C/ convection oven: 175 °C/ gas: level 3) for approx. 10 minutes. Remove baking paper and peas and bake the tartlets for another 5 minutes at the same temperature. Let the tartlets cool down a bit, then remove them from the tartlets and let them cool down
Fill the rhubarb compote into the tartlets and chill for about 1 hour. Sieve 75 g icing sugar into a bowl. Beat the egg white until stiff, slowly pour in the icing sugar. Spread the meringue mixture loosely over the cream in the tartlets. Bake in the preheated oven (electric cooker: 225 °C/ convection oven: 200 °C/ gas: level 4) for about 5 minutes until the tips turn brownish
waiting time approx. 1 1/2 hours