In a large mixing bowl, combine all-purpose flour and granulated sugar, mixing well. Cut in the cold unsalted butter until the mixture resembles coarse crumbs. Stir in the egg yolk and enough ice water until the dough forms. Shape into a disk, wrap in plastic, and refrigerate for 30 minutes.

Preheat your oven to 350°F (175°C).

Peel, core, and slice the apples into thin pieces. Toss with brown sugar, cinnamon, and lemon juice, ensuring even coating.

Roll out the chilled tart dough into a circle about 1/8 inch thick. Transfer it into the tart pan and trim excess dough.

Line the tart crust with parchment paper and fill with pie weights. Bake for 15 minutes, then remove weights and parchment, baking for another 10 minutes until golden brown.

In a medium saucepan over medium heat, add granulated sugar. Stir constantly until melted and amber-colored. Whisk in unsalted butter and heavy cream until smooth. Stir in sea salt and cool slightly.

Remove the baked crust, cool slightly, and arrange the apple slices. Drizzle with warm salted caramel sauce.

Bake the assembled tarts for 15 to 20 minutes until apples are tender and caramel bubbles slightly.

Let cool for 15 to 20 minutes before serving.

Drizzle remaining salted caramel sauce before serving. Pair with vanilla ice cream or whipped cream.