Using parchment/greaseproof paper, line the tart tin. (you can blind bake the pastry using ceramic cooking beans instead of parchment paper)
Roll the pastry dough so tat it is slightly larger than the tray. When the correct size, Gently roll the pastry onto your rolling pin and lay over the pan.
Gently lift each side so you can push the pastry into the pan making sure it is all covered. Using a sharp knife carfully trim off any excess around the edges.
Place to one side in a cold place or in the fridge while the filling is prepared.
Core and peel the apples.
Cut the apple in half and slice each other into small wedges.
Place the slices into the pastry dish form the outside moving towards the centre. When one layer is complete start again until all of the apples are used or the the apples have reached the top of the pastry.
Place little knobs of butter about the pan and sprinkle with the granulated sugar.
Place in the preheated oven for about 50 - 55 minutes until the pastry and apples start to brown.
Once the tart has cooked, add the jam and run to a small pan and gently heat until the mixture becomes thinner.
Using a pastry brush, coat the top of the tart with the jam and rum mixture.
Using the parchment paper, carefully raise the tart out of the pan and [place on a dish. Again Carefully peel the parchment paper away form the tart so it does not stick.
Allow to cool down naturally and serve either warmed or cool.