Preheat oven to 170C/325F/gas 3.
Grease the tart tin with butter.
To make the pastry sift the flour and salt into a large mixing bowl or food processor bowl.
Add the butter and then rub in (or process if using food processor) until the mixture resembles fine breadcrumbs.
Place the egg yolk in a cup and add the ice cold water and whisk together.
Add to the pastry mix and bring together to make a dough adding more water if the dough is too dry. If using a processor add the egg mixture and whizz until the mixture forms a ball of dough.
Wrap the dough in clingfilm and place in the fridge for 30 minutes.
Remove from the fridge and place on a lightly floured work surface. Roll out and line the tart tin with it. Place in the fridge for half an hour.
Remove the chilled tart tin from the fridge. Scrunch up a large piece of baking paper, open it out and place over the pastry. Fill with baking beans and bake in the preheated oven for 15 minutes.
Take out of the oven, remove the paper and baking beans and brush the pastry with the beaten egg. Return to the oven for a further 10 minutes.
Remove from the oven and set aside to cool.
To make the filling, place the apple in a saucepan with a little water and heat until the apple flesh has broken down and you have a fairly stiff apple paste. You will need to stir it regularly to stop the apple purée sticking to the bottom of the pan and burning.
Place the milk, rice and lemon peel into the other saucepan and bring to the boil.
Reduce the heat and simmer for half an hour stirring continuously (as you would to make a risotto) until the rice is tender and you have a creamy rice pudding. If the desired consistency is reached before the rice is tender just add more milk and keep stirring.
Pour the rice pudding and apple paste into the mixing bowl and beat together thoroughly.
Add the wine, egg yolks and mixed peel and beat together with the wooden spoon.
Place the filling into the prepared pastry shell and place in the oven for 35 to 40 minutes until the filling is golden.
Meanwhile make the sauce by placing the ingredients in a saucepan and simmering gently until thickened.
Remove the ‘pudding’ from the oven and allow to cool slightly before dusting with icing sugar and transferring to a serving plate. Place the sauce in a small jug and serve alongside the ‘pudding’.
