Jaffa Squares

1 packet vanilla wine biscuits
3 tablespoons cocoa
120g butter
1/2 cup sweetened condensed milk
1 orange

Process the biscuits in a food processor until reduced to crumbs. Add the cocoa and the grated rind of the orange and blend for a few seconds. Place the condensed milk and butter in a saucepan and gently heat until the butter is melted (this step can be done in a bowl in the microwave oven, if desired). Pour over the biscuit mix and process again to mix well.
Press into a lightly buttered sponge roll tin and refrigerate until set. Ice with a chocolate icing made with:

1 1/2 cups icing sugar
1 tablespoon butter
sufficient orange juice to mix