Trim the cores and toss apple quarters in a large mixing bowl with lemon juice and 1/2 cup sugar... let sit 30 mins

Preheat the oven to 375 f and place a rack in the center... place a 9-inch cast iron or ovenproof nonstick skillet over medium heat. Add 4 tablespoons butter. Stir to melt. Add 1 cup sugar with 4 tablespoons of juices from the apples. Stir to combine. Cook the mixture over medium low... stir occasionally till pale caramel color

Remove skillet from heat and carefully add the apple quarters, arranging them flat side up in concentric circles. Pack them tightly and layer as needed. Cut the remaining 2 tablespoons of butter into 1/4 inches and scatter over apples

Heat skillet over medium low head and let caramel turn to deep amber about 18-20 mins while apples cook.. occasionally spoon the caramel over them... and turn the skillet as needed for even cooking.

Lightly flour a work surface and place the thawed puff pastry in the center... use the rolling pin to 1/4 inch thick. Using a 10=inch cake pan as a template for size... cut around the pastry... and place the pastry dough circle over the apples in the skillet. Tuck the edges between the apples and the skillet.... cook in preheated oven till pastry rises and turns golden brown about 30-40 minutes... remove from oven and let cool. Place on a round serving plate... flip upside down... rearrange apples if they slide around after being flipped... cut tart into wedges and serve with a dollop of whipped cream or ice cream... YUM!!!!