Butter Cake with Kahlua Chocolate Frosting

Bahan-bahan (8 porsi)

• 250 g salted butter (softened)
• 1 1/2 cups caster sugar
• 3 eggs (extra large)
• 1 egg yolk (extra large)
• 3 cups self-raising flour
• 1 1/2 cups buttermilk
• 1 tbsp vanilla extract
• 1 cup icing sugar (chilled)
• 300 ml thickened cream (chilled)
• 1/3 cup unsweetened cocoa powder
• 50 ml Kahlua