Preparation
Preheat the oven to 180 °C (top and bottom heat).
Mix all the base ingredients together until smooth. Spread the dough evenly onto a baking tray lined with parchment paper.
Bake the base for 15 minutes.
Meanwhile, prepare the pudding filling: Use the 625 ml milk (note: do not follow the milk amount on the pudding package). Cook the pudding powder with the milk and sugar according to the package instructions. Stir continuously as the pudding thickens immediately after adding the powder.
Let the pudding cool slightly—but not completely—to avoid lumps. Then gently mix in the sour cream and egg yolks. Spread this creamy mixture evenly over the baked base.
Scatter the sour cherries (reserving the juice) evenly over the filling.
Return the cake to the oven and bake for another 15 minutes at 180 °C.