Tiramisu Cake from The Birthday Cake Book by Fiona Cairns

Ingredients

• 15-20 chocolate-covered coffee beans
• 30 g 70% cocoa solids chocolate, finely grated
• 2 tbsp cocoa powder
• 3 tbsp Tia Maria, dark rum or Kahlua
• 3 tbsp very strong black coffee (espresso or instant), cooled
• 1 tsp vanilla extract
• 50 g light muscovado sugar
• 200 ml double cream, very lightly whipped
• 2 tbsp very strong black coffee (espresso or instant), cooled
• 250 g mascarpone
• 225 g golden caster sugar
• 4 eggs, lightly beaten
• 225 g self-raising flour
• 1 tsp baking powder
• 225 g unsalted butter, really soft, diced, plus more for the tins