- Preheat oven to 180°C/325°F/Gas 4. Grease and base line a 20cms/8" deep cake tin.
- Cream butter and sugar until light and fluffy. Alternately add the flour and the eggs mixing well after each addition.
- Divide the mixture in half. Add the cocoa to one half and mix well.
- Then drop spoonfuls of the mixtures into the prepared tin. Put a knife into the mixture and draw it back and forth to make a marbled effect.
- Smooth the top bake for 40 to45 minutes until risen and a skewer inserted into the centre come out clean.
Allow to cool then remove from the tin. When cold, drizzle the top with the melted chocolate. Melt the chocolate separately.