Preheat oven to 350 degrees F. Roll the dough into six discs (you may have some dough left over) about 6 inches in diameter. Place the discs onto a cookie sheet. Spread one tablespoon of apple jelly on each disc and place one or two apple slices on top of the jelly. Fold the dough over the apple slices. Brush the tarts lightly with the beaten egg. Bake tarts for 13 to 15 minutes.
To Plate: The tarts can be served warm or at room temperature, with your favorite ice cream on top.
Reduce the cider to one cup in a pot over medium heat. The cider should be mahogany in color and the consistency of a sauce. Cool in the refrigerator.
Place flour and sugar in a bowl, stir together and make a well in the mixture. In a separate bowl, beat two eggs, egg yolk and butter together, then add the cinnamon and salt. Pour the egg mixture in the well and with your hands blend the mixture together until it forms a dough. If the dough is too sticky, add a bit more flour. Knead the dough for a couple of minutes. Place the dough in the refrigerator for 15 minutes.