Drain the apricots. Mix quark, milk, oil, 100 grams of sugar and lemon peel. Mix flour and baking powder, add to the quark mixture and knead to a smooth dough. Roll out 2/3 of the dough, on a floured work surface to form a rectangle (36 by 40 centimetres).
Line a greased fat pan (31 by 39 centimetres) sprinkled with breadcrumbs. Roll out the rest of the dough into a rectangle (32 by 30 centimetres) on a floured work surface.
Roll over the dough with the grid roller two and a half times the width. For the icing, stir the remaining sugar, vanillin sugar, sour cream, eggs and starch until smooth. Pour onto the dough and cover with apricots.
Carefully pull the dough grids apart, fold them and place them over the apricots. Press down on the edge. Mix egg yolk and cream and brush the grid with it. Sprinkle with sugar crystals. Bake in the preheated oven (electric oven: 175°C/ gas: level 2) for 30 minutes and let cool off.
Makes 25 pieces.