peel, cut in half and core the apples. (let me make a note here, avoid the tmptation to use other cooking or baking apples red delicious hold there shape and is the best for this recipe.) I usually have a large bowl of water with the juice of one lemon that I add the apple halve to as I process them.
Turn on the oven to 400 degrees.
melt the butter in the bottom of a large 12-14 in heavy skillet (This will go in the oven later so it must be all metal). Sprinkle the sugar over the butter, stand the apples on end to make a ring aound the skillet's outside edge then make another ring in the center, pack the apple in so that they are really tight. if you have left over apples you can add them when the ones in the skillet begin to cook.
cook the apples and sugar until the sugar is a rich deep caramel color. this will take some time. shake the pan gentley to make sure the apples don't stick or burn in spots. But hold out until the sugar goes to a full deep caramel color.
while the apples are cooking sprinkle flour on your work surface and roll the puff pastry out into a circle the size of your skillet, trim as needed. I stack the two pieces of dough from the package on top of each other before I roll the dough out if I'm making a really big skillet or if I am making a smaller pan I just use one piece of dough. You may also use a pie crust in place of the puff pastry if you like. Both work just as well.
when the caramelized sugar is a rich warm brown under all the apples remove the pan from the heat. Place the puff dough circle over the top of the apples and tuck the sides inside the lip of the skillet vent the dough by piercing it a few times with a small knife. Carefuly place the oven proof skillet in the preheated oven. bake for 50-60 minutes.
Carefully remove the skillet from the oven. give a gentle shake to loosen the apples. place a large platter over the skillet and very very carefully flip the apple tart onto the serving plater. (the sugar in the pan will be molten hot and may ooze onto your arms if you are not extremly careful)so sandwich the pan and plate togher and hold tightly as you flip it over very quickly.
the dessert is ready to be served. Or you can serve it at room temperature.
It's fabulous all by it's self or may be served with a caramel sauce or Anglaise Sause or even vanilla ice cream.