Aldo Zilli's sugared chestnut & coffee cake

Aldo says: "I am not the best at making cakes, but this one is so simple you cannot go wrong. Also in its favour - it can be made well in advance."

Serves: 8-12
Preparation time: 10 minutes
Cooking time: 45 minutes

What you need:

Preheat the oven to 200˚C/fan oven 180˚C/Gas Mark 6.
Lightly grease and line the base of a 20 cm square cake tin.
Place the chocolate in a heatproof bowl with the margarine and coffee. Place over a pan of simmering water and heat gently until melted, stirring occasionally.
Place the cocoa powder in a large bowl with the egg yolks and chestnut purée. Beat until smooth. Stir the chocolate mixture into the chestnut purée mixture.
In a separate bowl whisk the egg whites until stiff, then fold into the chestnut mixture using a large metal spoon. Spoon into the prepared tin and level the surface.
Bake the cake for 30-35 minutes until it is dark brown and firm to the touch. Allow to cool in the tin for 10 minutes then turn out. Leave to cool.
Decorate with the sugared chestnuts and dust with icing sugar or cocoa powder to serve.