Kiev Cake | Ukrainian Hazelnut Meringue Layer Cake

Toast the hazelnuts at 160°C / 320°F for 10 minutes, until their skins crack and the centers turn light brown. While they are hot, rub them in a towel to remove the skins. Grind 150 g coarsely in a food processor; chop the 40 g reserved for the edges into larger pieces with a knife.

In a clean, dry, grease-free bowl, beat the egg whites at medium speed until soft peaks form. Add the sugar one tablespoon at a time, then continue beating at high speed for 8–10 minutes, until the meringue is glossy and forms stiff peaks that do not droop from the whisk. You should not feel any sugar grains when rubbing a little between your fingers.

Mix the coarsely ground hazelnuts with the flour and vanillin. Fold this mixture into the meringue in three additions, using a spatula and sweeping from the bottom upward. Do not stir; deflated meringue will spread in the oven.

Draw two 22 cm circles on parchment paper and turn the paper over. Divide the meringue evenly between the circles and smooth it with a spatula to 1.5 cm thick.

For this recipe, keep the oven at 150°C / 300°F so the meringue dries inside without browning; at a higher temperature, the sugar caramelizes and the meringue turns brown. Bake the disks at 150°C / 300°F for 2 hours. They should be cream-colored and sound hollow when tapped with a finger. Do not try to remove them from the parchment while hot.

Whisk the milk, egg, and sugar in a small saucepan. Cook over low heat, stirring constantly, for 7–8 minutes, until thickened enough to coat the back of a spoon (82–84°C / 180–183°F). Do not let it boil, or the egg will curdle. Let the custard cool completely. Beat the butter for 5 minutes until pale, then add the cooled custard one spoonful at a time, beating until smooth and glossy. Set aside one-quarter of the buttercream and mix it with the cocoa and vanillin.

Turn the meringue rounds over and gently peel away the parchment. Trim the edges with a serrated knife and save the crumbs. Spread half of the white buttercream over the first round and top with the second. Spread the remaining white buttercream thinly over the top and sides. Press the chopped hazelnuts and meringue crumbs onto the sides. Pipe the cocoa buttercream on top and dust with powdered sugar.

Once the cake has rested, cut it with a serrated knife dipped in hot water and wiped dry, using a sawing motion. Pressing down can crack the meringue.