Chocolate traybake with feather icing

This chocolate traybake is topped with a milk chocolate icing feathered with white chocolate. This is a great cake to share for a birthday party. Decorate it as you like - try topping it with sweets, chopped chocolate bars or marshmallows!

Equipment and preparation: you will need a small piping bag and a 30x23cm/12x9in traybake tin greased and base lined with baking parchment.