To make the shortbread crust
1-Preheat the oven to 350°F (180°C): Preheat the oven to 350°F (180°C). Line a 9×13-inch baking pan with parchment paper, making sure to leave some overhang for easy removal, and set aside.
2-In the bowl of a stand mixer: In the bowl of a stand mixer fitted with the paddle attachment or in a large mixing bowl using a handheld mixer, beat the butter and sugar until well combined, about 2 minutes.
3-Mix in the egg yolks and salt: Mix in the egg yolks and salt until fully combined, stopping to scrape down the sides of the bowl as needed.
4-Add the flour and continue mixing on: Add the flour and continue mixing on low speed until the mixture starts to come together, but is still crumbly.
5-Scoop the crumbly mixture into the prepared: Scoop the crumbly mixture into the prepared baking pan and press it down into one even layer.
6-Bake for 23 to 28 minutes, or: Bake for 23 to 28 minutes, or until the top is set and the edges are lightly golden brown. Remove from the oven and set aside to cool completely on a wire rack. If needed, you can place it in the refrigerator on a wire rack to speed up the cooling process.

To make the caramel
7-In a large saucepan, combine the sweetened: In a large saucepan, combine the sweetened condensed milk, brown sugar, sliced butter, and corn syrup.
8-Place over medium heat, whisking frequently until: Place over medium heat, whisking frequently until it comes to a boil. Continue cooking for 8 to 13 minutes, whisking constantly, until the mixture thickens, starts to pull away from the sides of the pan, and turns a caramel color. I recommend wearing an oven mitt while you are whisking the mixture to avoid any hot splatters. You can test the mixture to make sure it’s done by filling a glass with cold water and dropping a small spoonful of caramel into it. If you can form a soft ball with the mixture, then it’s ready. If you can’t, keep on cooking the caramel.
9-Remove from the heat and stir in: Remove from the heat and stir in the vanilla extract and salt until fully combined.
10-Pour the caramel over the cooled shortbread: Pour the caramel over the cooled shortbread crust and spread it around into one even layer. Refrigerate for 1 hour or until the caramel is mostly set.

To make the ganache
11-Combine the chopped chocolate and heavy whipping: Combine the chopped chocolate and heavy whipping cream in a large heat-proof bowl. Microwave in 20-second increments, stirring well after each increment, until the chocolate is completely melted and smooth.
12-Remove the pan from the refrigerator, pour: Remove the pan from the refrigerator, pour the chocolate ganache on top, and spread around into one even layer. Sprinkle the top with sea salt.
13-Return to the refrigerator and chill for: Return to the refrigerator and chill for 1 to 2 hours or until the chocolate is set and firm.
14-Lift the bars out of the pan: Lift the bars out of the pan using the overhang from the parchment paper, slice into pieces, and serve.