🇭🇺 Hazelnut and Chocolate Layer Cake (Esterházy Torte)

Ingredients

For the Nut Layers

• 6 egg whites
• ¾ cup sugar
• 1 ½ cups finely ground hazelnuts (or almonds)
• 2 tbsp all-purpose flour
• 1 tsp vanilla extract
• Pinch of salt

For the Custard Buttercream

• 4 egg yolks
• ½ cup sugar
• 1 cup milk
• 2 tbsp cornstarch
• 200 g (7 oz) butter, softened
• 1 tsp vanilla extract

For the Glaze

• 1 cup powdered sugar
• 2 tbsp lemon juice or water
• 50 g (2 oz) melted dark chocolate