Preheat your oven to 350"F (175"C).

Line a 9x13-inch baking pan with parchment paper leaving an overhang on the sides for easy removal.

Combine crushed pretzels, melted unsalted butter and granulated sugar for the pretzel base and mix until well combined.

Press the pretzel mixture evenly into the bottom of the prepared baking pan to form the base layer.

Bake in the preheated oven for 10 minutes.

While the pretzel base is baking prepare the caramel layer in a saucepan over medium heat. Combine sweetened condensed milk, unsalted butter, and brown sugar. Stir constantly until the mixture thickens and turns a caramel color (about 10-15 minutes).

Remove the pretzelbase from the oven and pour the hot caramel mixture over the top spreading it into an even layer.

Return the pan to the oven and bake for an additional 12-15 minutes or until the caramel is bubbly and set.

Remove the pan from the oven and let it cool completely on a wire rack.

Once the caramel layer has cooled prepare the chocolate topping in a microwave-safe bowl. Combine semisweet chocolate chips and vegetable shortening. Microwave in 30-second intervals and stir between each interval until the chocolate is melted and smooth.

Pour the melted chocolate over the cooled caramel layer spreading it into an even layer with a spatula.

If desired sprinkle sea salt flakes over the top of the chocolate layer for a sweet and salty contrast.

Place the pan in the refrigerator for about 1 hour or until the chocolate layer is set.

Once set use the parchment paper overhang to lift the bars out of the pan. Cut into bars or squares using a sharp knife.

Serve and enjoy these irresistible Caramel Pretzel Crack Bars!