To make the shortbread cookie bars:

1. Toast the coconut in a large skillet over medium heat. Once you start to see the coconut browning, continue to stir constantly to prevent it from burning. After the coconut is toasted medium brown, remove it from the skillet and onto a baking sheet to begin cooling. Set the coconut aside.
2. Preheat the oven to 325 degrees and line a 9 x 13 baking pan with parchment paper. Alternatively, grease the pan with a flour based baking spray or butter. Set aside.
3. Sift the flour, cornstarch and salt together into a small bowl and set aside.
4. Add the 1 1/2 cup softened butter to a large bowl (I used a 6 quart size) along with the powdered sugar. Use an electric mixer to cream the butter and sugar together on medium high speed for 2 minutes. Scrape down the bowl with a spatula and continue to cream on high speed for another 2 minutes. The mixture should be light and fluffy.
5. Add the vanilla and mix until blended.
6. Add half of the flour mixture and mix on medium low speed until incorporated. Scrape down the bowl and add the remaining flour mixture, along with 3/4 cup of the toasted coconut. Mix on low speed until the dough clumps up together and there are no raw flour streaks or pockets remaining.
7. Press the shortbread dough into the prepared 9 x 13 pan, making sure to evenly pack it into a uniform layer. Use a fork to poke holes all over the dough and brush with the egg white.
8. Bake at 325 degrees for 27 minutes. If you want the bars to be more crisp, bake for 30 minutes. Allow the bars to cool completely, about 4 hours.

Make the chocolate and caramel coconut toppings:

1. Add 4 oz of the chopped chocolate to a small heatproof bowl and pour the heavy cream over the chocolate. Microwave on full power for 30 seconds, and stir well to distribute the heat. Return to the microwave and heat for another 30 seconds, stirring again. If all of the chocolate isn’t melted and smooth, microwave for another 15 seconds. Don’t overheat the mixture, or it will break and seize. If it does, allow it to cool a bit and continue stirring to bring it back together.
2. Once the chocolate is melted and the mixture is smooth, spread evenly over the cooled shortbread bars. Refrigerate the pan for another 2 hours, or until the ganache is set.
3. Halfway through the chocolate’s chilling time, (1 hour) make the salted caramel. Add the cup of granulated sugar to a heavy bottomed saucepan (I used a 3 quart size) and set over medium high heat.
4. Stir the sugar constantly with a heatproof spatula or spoon until it begins to melt and clump up. Continue stirring constantly until the sugar melts completely into an amber colored liquid and there are no remaining clumps of sugar. Switch to a whisk for the rest of the process.
5. Working quickly, add the 6 TB of room temperature butter and whisk vigorously to incorporate. The sugar will sizzle and bubble up quite a bit when you add the butter, this is normal. Keep whisking!
6. After the mixture relaxes a bit and the butter has been incorporated, allow the caramel to cook for one minute, undisturbed. Slowly stream in the cream, whisking constantly. The caramel will bubble up again, this is also normal.
7. After adding the cream, continue to whisk for a few more seconds and allow the mixture to calm a bit. Then let it boil for one more minute without touching it.
8. Remove the caramel from the heat and whisk in the salt. Allow it to cool and thicken slightly while the chocolate finishes setting up in the fridge.
9. After the 2 hours are up, stir another 3/4 cup of toasted coconut into the salted caramel. Spread the caramel/coconut mixture on top of the chocolate and sprinkle with the remaining 3/4 cup toasted coconut.
10. Heat the remaining 2 oz chopped chocolate for 30 seconds in the microwave and stir. Microwave for an additional 10-15 seconds as needed to completely melt the chocolate. Once completely melted, drizzle the chocolate over the bars.
11. Refrigerate for 2 hours before serving. Any leftover bars can be stored at room temperature once the chocolate and caramel have set up. Eat any leftovers within 3-4 days, or you can refrigerate the bars for a few weeks. Bars will freeze for 6 months.