Chocolate Biscuit Cake

1/2 tsp butter, for greasing pan
8 ounces 'McVities' rich tea or 'Digestive' biscuits (I used Digestives)
4 tablespoons unsalted butter, softened
1/2 cup granulated sugar (I used just 1/4 and grinded it to a powder)
4 ounces good dark chocolate 113g
1 egg, beaten
8 ounces good dark chocolate, for icing
1 ounce good white chocolate, for decoration (I omitted this and use some dessicated coconut n nuts instead)

Optional (my suggestion):
4 oz or half a cup of crushed pistachios, hazelnuts, cashewnuts and almonds

Lightly grease a small 6" x 2 1/2" cake ring with 1/2 teaspoon butter, and place on a parchment-lined tray.

TIP: A cake ring is like a cake pan but without the bottom, so its just the circle. This will make it easier to remove the cake once it sets, so try and use something similar but if you don't have one, then line a bowl with aluminium, enough that the edges of foil extend outside the bowl so you can later lift the cake out of the bowl without destroying its' shape.

Break each of the biscuits into almond-sized pieces by hand and set aside. Cream the butter and sugar in a bowl until the mixture is a light lemon colour.

Melt the 4 ounces of dark chocolate in a double boiler. Add the butter and sugar mixture to the chocolate, stirring constantly. Add the egg and continue stirring. Fold in the biscuit pieces until they are all coated with the chocolate mixture.

Add the crushed nuts for a fuller flavoured cake, if you desire.

Spoon the chocolate biscuit mixture into the prepared cake ring. Try to fill all of the gaps on the bottom of the ring, because this will be the top when it is unmolded. Chill the cake in the refrigerator for at least three hours or until it sets firmly.

Remove the cake from the refrigerator, and let it stand while you melt the 8 ounces of dark chocolate for icing. Slide the ring off the cake and turn the cake upside down onto a cooling rack.

Pour 8 ounces of melted dark chocolate over the cake, and smooth the tops and sides using a butter knife or offset spatula. Allow the chocolate icing to set at room temperature. Carefully run a knife around the bottom of the cake where it has stuck to the cooling rack, and transfer the cake to a cake dish. Melt the white chocolate and drizzle on top of the cake in a decorative pattern or garnish with nuts and dessicated coconut.