A German neighbour used to make a very simple and very good rhubarb cake. I remember it had a layer of cake batter, then a layer of cut-up rhubarb, and then, where one would often put streusel, she had a layer of custard-like kind (it had eggs and sugar, but I do not remember if anything else). Everything was assembled at once, and then baked. I wrote the recipe down and seems to have lost it.
Has anyone run across a cake recipe with the "custard" like topping I am describing? I can concoct a cake base, but I would like to get some idea of what goes in the topping? (I do not remember if it had whole eggs, or just yolks?).
Thank you in advance