Poppy Seed Cake with sour cream, inspired by Saxon and Thuringian baking tradition, with homemade poppy seed filling, cinnamon and lemon. Baked on a soft base beneath a delicate egg and cream topping, rich and aromatic.
Stir flour, margarine, sugar, egg, and baking powder until the batter is spreadable. Lightly grease the inside of the springform ring with rapeseed oil. Spread the batter in the pan and press down firmly, e.g., with a glass. Smooth the surface.
Poppy seed mixture
Bring milk, sugar, and vanilla sugar to a boil until the sugar dissolves. Remove from the heat. Stir in poppy seeds, honey, cinnamon, and lemon zest. Cover and let swell for 5 minutes. Consistency: spreadable, not runny. If too firm, add a little milk, wait briefly, and check again.
Poppy seed pudding layer
Cook a thick vanilla pudding from 650 ml milk and 55 g vanilla pudding powder (do not add extra sugar). As soon as it thickens noticeably, remove from the heat. Stir the entire poppy seed mixture into the hot pudding until smooth. Then quickly stir in 200 g sour cream. Spread the mixture over the base immediately and smooth it out. It should fall thickly from a spoon and not run. If it still feels too soft right after stirring, let it stand for a few minutes, it will set up.
First baking stage
Bake at 180 C for about 30 minutes, until the surface has visibly set and feels stable.
Prepare the sour cream egg layer
Separate the eggs. Mix the yolks with powdered sugar and 300 g sour cream until smooth. Beat the egg whites until stiff peaks form and fold them in carefully until the mixture looks even and no large streaks of egg white remain. Remove the pre-baked poppy seed cake from the oven, spread the sour cream egg layer on top, and smooth it out. When folding, mix only as long as needed.
Finish baking
Smooth the sour cream egg layer and bake the cake for another 20-25 minutes at 180°C (356°F). If the top browns too quickly, cover it loosely. Then turn off the oven and leave the door slightly ajar for 10 minutes, for example with the handle of a wooden spoon. After that, remove the cake and let it cool completely.