Hazelnut Layered Cake

Preheat the oven to 350°F (175°C). Prepare two round cake pans by greasing them lightly with butter and lining the bottoms with parchment paper.

In a clean, dry bowl, beat the 5 egg whites with an electric mixer until stiff peaks form, about 3-4 minutes.

Gradually add the confectioner's sugar to the egg whites while continuing to beat, incorporating it gently to maintain the airy texture. Beat until the mixture is thick and glossy.

Fold the roasted and ground hazelnuts and roasted and ground almonds into the meringue mixture using a rubber spatula, working gently to avoid deflating the egg whites.

Divide the batter evenly between the two prepared pans and smooth the tops with a spatula.

Bake in the preheated oven for 20-25 minutes until the cake layers are pale golden and a skewer inserted in the center comes out clean.

Remove the cake pans from the oven and allow them to cool for 5-10 minutes before turning out onto a wire rack to cool completely.

Once cooled, place one cake layer on a serving plate and spread a thin layer of softened butter between the two cake layers before topping with the second layer.

Dust the top of the hazelnut layered cake lightly with additional confectioner's sugar if desired before serving.