Classic French Opera Cake - Great Easy Recipe

Ingredients

• 6 large eggs
• 6 egg whites
• 1 cup (200g) granulated sugar
• 1 cup (100g) almond flour
• ⅔ cup (85g) all-purpose flour
• 3 tbsp unsalted butter, melted
• ½ tsp salt
• ½ cup (120ml) strong brewed espresso
• ½ cup (100g) granulated sugar
• 1 tsp coffee liqueur (optional)
• 4 large egg yolks
• ¾ cup (150g) granulated sugar
• ¼ cup (60ml) water
• 1 cup (226g) unsalted butter, softened
• 1 tbsp instant espresso powder
• 1 tsp vanilla extract
• 8 oz (225g) dark chocolate, chopped
• ¾ cup (180ml) heavy cream
• 1 tbsp unsalted butter
• 5 oz (140g) dark chocolate, chopped
• 1 tbsp vegetable oil or melted butter