For the barmbrack, put the dried fruit in a bowl and pour over the cold tea and whiskey. Cover and leave to soak overnight.
Preheat the oven to 170C/150C Fan/Gas 3. Butter and line a 900g/2lb loaf tin.
Put the flour, baking powder, sugar and mixed spice in a mixing bowl. Make a well in the middle and crack in the egg. Mix well using a wooden spoon. Add a little liquid from the fruit mixture and stir. Continue adding liquid and stirring until you have a wet dough – you may not need all the liquid. Drain the dried fruit and mix it into the dough until well combined.
Spoon the dough into the prepared loaf tin and level off the top. Bake on the middle shelf of the oven for 1 hour, or until a skewer inserted comes out clean. Leave to cool in the tin slightly, then turn out onto a wire rack to cool completely.
For the parfait, preheat the oven to 200C/180C Fan/Gas 6. Cut the crusts off the bambrack, then crumble 175g/6oz of the barmbrack into a roasting tin. Sprinkle over 1 tablespoon of sugar. Bake for 10 minutes, or until crisp, then leave to cool.
Whisk the egg yolks with the remaining 1 tablespoon of sugar.
Put the milk, 85ml/3fl oz cream and the piece of vanilla pod in a heavy-bottomed saucepan and bring to the boil. Remove from the heat and pour over the yolk mixture, whisking all the time. Return the pan to the heat and cook gently until the custard coats the back of the spoon, stirring.
Strain the custard into a bowl through a fine sieve. Leave to cool.
Melt the chocolate in a heatproof bowl over a pan of gently simmering water, making sure the bowl doesn’t touch the water. Fold the melted chocolate and crumbs into the custard, cover and chill for 30 minutes.
Whisk the remaining cream until soft peaks form. Fold the cream and whiskey into the custard mixture. Pour into six plastic see-through cups, cover and freeze for 2-3 hours, or overnight if you have the time.
For the prunes, bring 200ml/7fl oz water to the boil in a medium saucepan. Add the orange zest and juice and the sugar and return to the boil. Add the prunes, cover and simmer for 20 minutes, or until softened. Stir in the whiskey. Set aside to cool.
To serve, spoon the prune mixture on top of each cup and grate a little orange zest on top.