Ingredients:
For the Sponge Cake Layers:
• 8 large eggs, separated
• 1 cup (200g) granulated sugar
• 1 cup (125g) all-purpose flour, sifted
• 1/4 cup (30g) unsalted butter, melted
For the Chocolate Buttercream:
• 1 cup (225g) unsalted butter, softened
• 1 1/2 cups (180g) powdered sugar, sifted
• 4 oz (120g) dark chocolate, melted and cooled
• 2 tsp vanilla extract
For the Caramel Glaze:
• 1 cup (200g) granulated sugar
• 1 tbsp lemon juice
• Butter, for greasing the knife
For Decoration:
• Chocolate buttercream (reserved from filling)
• Small caramel triangles (optional)