1. Preheat oven to 160˚C. Grease a 20 × 30cm shallow tin.
2. Put dates, butter and milk in a medium saucepan. Gently heat until butter has melted. Cool.
3. Add cake mix and eggs to dates, beating well to combine. Pour mixture into the tin.
4. Bake for 20 minutes or until cake springs back when lightly touched. Leave to cool.
5. To make icing put brown sugar, butter and milk in a saucepan. Cook over a gentle heat, stirring constantly until sugar has dissolved.
6. Remove from heat and sift in icing sugar, mixing to a smooth paste. If necessary, add more milk to a give a spreading consistency. Spread slice with icing.
7. When icing is almost set cut into bars with a hot knife. Set aside until cold.