Prepare the metal cake ring by greasing with butter and lining the sides and the bottom with baking paper. Place the lined ring on to a flat tray and leave to one side until required.

Break the biscuits into small pieces, around 1–2cm in size. Do not place into a processor – the biscuits should not become crumbs.

Place the softened butter and the sugar into a bowl and cream together until light and fluffy.

Melt the chocolate either in the microwave or over a simmering saucepan of water. Once melted, pour the chocolate on to the butter and sugar and mix thoroughly.

Finally, add the water and then the broken biscuit pieces. Stir well to make sure that all the biscuit pieces are coated with the chocolate mix.

Place the mixture into the lined cake ring and carefully but firmly push it down to create an even texture. Place the cake into the fridge to chill until the chocolate becomes firm. This could take up to 30 minutes.

To prepare the ganache for the cake covering, place the chopped chocolate into a bowl and pour the whipping cream into a saucepan.

Bring the cream to a simmer and then pour over the chopped chocolate. Carefully stir until the chocolate has completely melted and the ganache is smoothly blended.

Remove the chocolate biscuit cake from the fridge and from the cake ring. Place on to a wire rack with a tray beneath to collect the excess ganache.

Carefully coat the chocolate biscuit cake with the warm ganache, making sure that all of the cake is evenly coated. Allow to set fully before moving to your service plate and decorating as desired.