How to make the chocolate filling:

Place the butterscotch chocolate in a medium sized heatproof bowl, set aside.

Heat double cream in a small saucepan on medium high heat just until cream starts to bubble around the edges. Remove from heat and pour cream over the chocolate. Stir with a whisk or fork until all of the chocolate has melted and the mixture is smooth. If the chocolate stops melting, place the bowl over a pot of barely simmering water, continue stirring until the heat from the steam has melted all of the chocolate and the mixture is smooth.

Leave at room temperature for about 30 minutes to cool, and then place in the fridge and leave to chill while you make the cake.

How to make the cake:

Preheat the oven to 180°C/160°C fan assisted/gas 4.

Grease 3 x 20cm (8 inch) round cake tins and line the bottom with parchment paper.

Tip: for a more even rise, wrap doubled strips of old kitchen towels that have been run under water and then lightly wrung out around each tin, securing the cloth with metal pins or paperclips.

Sieve together the flour, cocoa powder, baking powder and baking soda in a large bowl. Whisk in caster sugar and salt. In a medium sized jug, whisk together the wet ingredients except the boiling water. Add to the dry ingredients and mix with a whisk or electric mixer just until mixture is smooth.

Slowly add the boiling water and mix until well combined –the batter will be liquid.

Pour the batter evenly between cake tins and bake in preheated oven until cake layers spring back when lightly pressed or toothpick inserted comes out clean, about 30-40 minutes. Remove from oven and leave to cool for about 10 minutes on a wire rack, and then turn cakes out onto a wire rack and leave to cool completely.

How to make the marscapone filling:

Once sponge layers are completely cool, prepare the mascarpone filling.

Place mascarpone in a medium sized bowl and give a quick mix with a whisk just to loosen it up. Add the rest of the ingredients and stir with whisk until combined and mixture has slightly thickened and is a good spreading consistency that will hold its shape.

If the chocolate filling is too firm to spread, melt it very slightly in the microwave on a low setting for short bursts. Once it's the correct consistency, give it a quick mix to make sure the butterscotch bits are mixed through as they may have settled at the bottom of the bowl.

Spread 1/3 of the chocolate mixture over the top of each sponge with a spatula, blunt knife or the back of a spoon. Do the same with 1/3 of the mascarpone cream filling. Place one of the sponge layers with toppings on a serving plate and then carefully stack the remaining two on top, always with the mascarpone filling as the top layer.

To decorate, place Butlers dark chocolate in the microwave and heat on lowest power setting in 10 second bursts just until it's softened slightly, but isn't melting. Shave the chocolate with a vegetable peeler or a sharp knife. Decorate top of the cake with the chocolate shavings, and any other additions like gold sprinkles or balls.

Keep refrigerated, but leave at room temperature for an hour before serving. Butlers Showstopper Cake will keep for 2 days in an airtight container in the fridge.

Our top tips!

The chocolate sponge can be made up to 2 days ahead. Loosely wrap sponges with parchment paper and store in airtight freezer bags or in a large airtight container until ready to assemble.

The chocolate filling can also be made up to 2 days ahead and kept in the fridge until needed. Leave out for 2-3 hours to soften, or heat in the microwave on lowest power setting in bursts of 10 seconds, mixing in between until soft enough to spread.