one 20 cm (8 inch) round cake (we used chocolate, but you could use butter, mud or coconut cake)
60 g (2 oz) white chocolate melts
60 g (2 oz) milk chocolate melts
60 g (2 oz) dark chocolate melts
Milk chocolate glaze
250 g (8 oz) milk chocolate,
chopped 125 ml (4 fl oz) cream
1 teaspoons glycerine
2 teaspoons light corn syrup
1 To make the chocolate waves, cut longs strips of shiny contact about 3-4 cm (2 inches) wide. You can make them all the same length or vary them. Melt the white, milk and dark chocolate melts separately: put the melts in a heatproof bowl, bring a small pan of water to a simmer, remove from the heat and place the bowl over the pan (don't let the bottom of the bowl sit in the water). Stir the chocolate over the hot water until melted. Spread a little of the chocolate roughly down each strip of contact (use the shiny side of the contact). Drape the strips over a rolling pin, or different sized bottles to bend them and give interesting shapes. Leave the chocolate to set completely.
2 To make the milk chocolate glaze, put the chocolate, cream, glycerine and corn syrup in a heatproof bowl. Bring a small pan of water to a simmer, remove from the heat and place the bowl over the pan (don't let the bottom of the bowl sit in the water). Stir over the hot water until the glaze is smooth. Alternatively, melt in the microwave for 30 seconds on High.
3 Using a serrated knife, cut the dome off the top of the cake to level the surface. Turn the cake upside down on a wire rack, so that the flat base of the cake becomes the top.
Stand the wire rack over a tray. Pour the chocolate glaze over the top of the cake, then tap the tray on the bench to make the glaze run evenly down the side of the cake. Leave the glaze to set—if the weather's warm you may need to put the cake in the fridge. Scrape the glaze from the tray and gently reheat until smooth (you may need to strain the glaze if there are cake crumbs in it). Pour the glaze over the cake again, tapping the tray to level the surface, and allow to set again. Carefully lift the cake from the wire rack onto a serving plate.
4 When the glaze has completely set, carefully peel the contact from the chocolate waves and pile up on top of the cake.
Spread the melted chocolate over the strips of contact.
Drape the chocolate strips over different sized curved objects, to make them curl.
Gently reheat the glaze until smooth, then pour over the top of the cake again.
When the chocolate has completely set, peel the backing from the waves.
Ahead of time: The cake can be glazed up to a day in advance, and the chocolate waves made up to 4 days in advance and stored in an airtight container in a cool dark place. Pile the waves on top of the cake just before serving.