Place the puff pastry slices next to each other and let them thaw at room temperature for about 10 minutes. Mix quark, vanilla sugar, sugar, pudding powder, 1 egg and poppy seed until smooth. Drain the cherries on a sieve.
Brush the puff pastry slices with a little water, place them on top of each other again. Roll out into a rectangle (approx. 40 x 45 cm) on a floured work surface. Sprinkle with breadcrumbs. Spread the quark mixture on top and smooth it down, leaving a margin of about 2 cm on the shorter sides.
Spread the cherries over the curd mixture. Fold uncoated edges over the curd mixture. Roll up from the long side. Place diagonally on a baking tray lined with baking paper. Whisk 1 egg and brush the strudel with it.
Sprinkle with sugar crystals. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 35-40 minutes. Let them cool down. Serve decorated with melissa.