A rustic, cake-version of the French mille-feuille that some say was eaten to celebrate the Russian defeat of Napoleon in 1812, it's made of twelve layers of pastry—each rolled and baked individually—swiped with vanilla bean-flecked pastry cream and stacked precariously high.
When you slice into the cake, each cross section is striated with layers of flaky and buttery pastry, cool and sweet cream. If you let the cake sit assembled overnight or for at least a few hours (Olia does, her mother does not), the inside will be soft and pudding-like while the outer perimeter maintains some crispness.
Slightly adapted from Mamushka by Olia Hercules. —Sarah Jampel