My oldest daughter brought a mimeographed copy of this recipe home from school, so I took the liberty of translating it from Hebrew and posting it.
Combine eggs, vanilla extract and sugar, add mayonnaise and cocoa, mix well and then add flour, baking powder and baking soda, and add water last. Bake the cake at 180^C (356 F) within an hour. Good luck and b'teavon!