Line a six-inch square tin with greaseproof paper. Heat the oven to 375°F, 190°C, gas mark 5. Put the treacle and the lard in a small saucepan and melt. Sieve all the dry ingredients together and add the sugar to them with the fruit. Beat up the egg in a separate basin and add the milk to it. Pour into the centre of the flour and stir all together with the melted lard mixture. Mix thoroughly and turn into the prepared tin. Bake in the centre of the oven for 30-40 minutes, reducing heat slightly after the first fifteen minutes.