Clean and wash the rhubarb, drain well and cut it into slices of about 2 cm thickness (results in about 1 kg). Mix the rhubarb and 150 g sugar in a large pot and let the juice steep for 20-30 minutes
Place flour, starch, butter, 1 tablespoon of water, 75 g sugar and 1 egg in a bowl. First knead with the dough hooks of the hand mixer, then with your hands to a smooth short pastry. Wrap in foil and chill for about 30 minutes
Bring the rhubarb to the boil over a high heat while stirring carefully. Steam rhubarb pieces for 4-5 minutes until soft and glassy, but do not let them disintegrate. Drain the rhubarb on a sieve, collect the juice and use it for other purposes
Grease a springform pan (26 cm Ø) and dust with flour. Roll out about half of the shortcrust pastry on the bottom of the springform pan. Place the edge of the springform pan around the base. Form 2 rolls (approx. 36 cm each) from the remaining dough, place them in the form and press them 3-4 cm high onto the edge of the form. Prick the pastry base several times with a fork. In front
Wash the lemon thoroughly and finely grate about half of the peel. Separate 2 eggs. Put quark, egg yolks, 100 g sugar, almonds and lemon rind into a mixing bowl and stir until smooth. Beat the egg whites until stiff, then add 25 g of sugar. fold the beaten egg white into the quark mixture
Remove the pre-baked shortcrust pastry base from the oven and turn down the temperature (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2). First put the rhubarb, then the quark mixture on the shortcrust pastry base and spread. Bake on the lower rack for 30-40 minutes. Cool the cake in the tin on a cake rack. Then remove from the tin and allow to cool completely. Sprinkle as desired with toasted almond flakes and icing sugar. Whipped cream tastes good with it
waiting time approx. 2 hours