For the sponge: 340g plain flour
130g cocoa powder
2¼ teaspoons baking powder
2¼ teaspoons baking soda
525g caster sugar
½ teaspoon salt
3 eggs
375ml milk
190ml sunflower or canola oil
2 teaspoons vanilla extract
375ml boiling water
For the chocolate filling:
3 x 100g Butlers Milk Chocolate Honeycomb Crisp Bar, roughly chopped
225ml double cream
For the mascarpone filling: :
500g mascarpone cheese, chilled
4 tablespoons caster sugar
1 teaspoon vanilla extract or paste
125ml double cream
100g Butlers 70% Dark Chocolate Bar, for decorating