Grated Cake with Blueberries and Quark

Whip the softened butter together with granulated sugar into a light and fluffy foam; this takes several minutes. Add the egg yolk and whisk until smooth. Now add the flour mixed with cinnamon, cardamom, and salt, and use a spatula or your hands to work it into a smooth and only slightly sticky dough. Wrap in cling film and place in the freezer to firm up for at least 2 hours.

Once the dough is cold, preheat the oven to 180 °C and line a baking pan, approximately 20x20 cm, with baking paper. Prepare the filling. Mix the quark with the egg yolk, powdered sugar, starch, and scraped vanilla bean. In a separate bowl, whip the egg whites with a pinch of salt into very stiff peaks and carefully fold them into the quark mixture.

Coarsely grate the frozen dough and sprinkle approximately 2/3 of it onto the bottom of the prepared pan. Then pour the quark filling over it, smooth it out, and sprinkle with blueberries. Finally, cover with the remaining grated dough.