• Preheat the oven to 350°F (175°C) and prepare an 8x8-inch baking pan by lining it with parchment paper or greasing it well.

For the Crust:

• In a medium bowl, combine the flour, sugar, and salt.
• Grate the chilled salt and incorporate it into the mixture using your hands until it becomes crumbly. Reserve ¾ cup of this mix.
• Press the remaining mixture evenly into the bottom of the pan to create a solid base.
• Bake for 20 minutes until it achieves a golden brown color, then remove from the oven and let cool.

For the Filling:

• While the crust cools, prepare the filling by mixing the chopped apples with sugar, flour, lemon juice, and cinnamon in a large bowl.
• In a saucepan over medium heat, melt the unsalted butter and then add the apple mixture. Cook for about 7-8 minutes until the apples become tender and the mixture thickens.
• Spread the cooked apple filling evenly over the baked crust.
• Top the apples with the reserved crust mixture, spreading it evenly.
• Return to the oven and bake for an additional 23-25 minutes or until the topping is golden brown.
• Let the bars cool completely before slicing into squares to serve.
• For an added delight, serve these delicious bars with a scoop of vanilla ice cream.